Chapter 50: Rectangle Properties
Learn Grade 4 mathematics with very-beginner explanations, original worked examples, practice, reasoning, and review.
Chapter Overview
This chapter teaches Rectangle Properties in original, simple language with step-by-step reasoning, worked examples, practice exercises, common mistakes, and review questions.
50.1 Recognizing rectangles
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Find the area of a 6 cm by 9 cm rectangle.
- Use area = length × width.
- 6 × 9 = 54.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 54 cm²
Worked Example 2
Problem: Find the area of a 8 cm by 3 cm rectangle.
- Use area = length × width.
- 8 × 3 = 24.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 24 cm²
Worked Example 3
Problem: Find the area of a 9 cm by 9 cm rectangle.
- Use area = length × width.
- 9 × 9 = 81.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 81 cm²
Worked Example 4
Problem: Find the area of a 7 cm by 3 cm rectangle.
- Use area = length × width.
- 7 × 3 = 21.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 21 cm²
Worked Example 5
Problem: Find the area of a 6 cm by 9 cm rectangle.
- Use area = length × width.
- 6 × 9 = 54.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 54 cm²
Worked Example 6
Problem: Find the area of a 7 cm by 3 cm rectangle.
- Use area = length × width.
- 7 × 3 = 21.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 21 cm²
Worked Example 7
Problem: Find the area of a 7 cm by 8 cm rectangle.
- Use area = length × width.
- 7 × 8 = 56.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 56 cm²
Worked Example 8
Problem: Find the area of a 5 cm by 6 cm rectangle.
- Use area = length × width.
- 5 × 6 = 30.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 30 cm²
Worked Example 9
Problem: Find the area of a 7 cm by 4 cm rectangle.
- Use area = length × width.
- 7 × 4 = 28.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 28 cm²
Worked Example 10
Problem: Find the area of a 11 cm by 9 cm rectangle.
- Use area = length × width.
- 11 × 9 = 99.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 99 cm²
Practice Exercise
Create and solve one new example of Recognizing rectangles. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.2 Four right angles
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Create a simple Grade 4 example about Four right angles using the numbers 10 and 3.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 2
Problem: Create a simple Grade 4 example about Four right angles using the numbers 2 and 3.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 3
Problem: Create a simple Grade 4 example about Four right angles using the numbers 10 and 11.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 4
Problem: Create a simple Grade 4 example about Four right angles using the numbers 7 and 7.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 5
Problem: Create a simple Grade 4 example about Four right angles using the numbers 4 and 18.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 6
Problem: Create a simple Grade 4 example about Four right angles using the numbers 13 and 8.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 7
Problem: Create a simple Grade 4 example about Four right angles using the numbers 11 and 19.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 8
Problem: Create a simple Grade 4 example about Four right angles using the numbers 4 and 20.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 9
Problem: Create a simple Grade 4 example about Four right angles using the numbers 16 and 13.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Worked Example 10
Problem: Create a simple Grade 4 example about Four right angles using the numbers 9 and 5.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Four right angles.
Practice Exercise
Create and solve one new example of Four right angles. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.3 Opposite sides of a rectangle
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Find the area of a 12 cm by 4 cm rectangle.
- Use area = length × width.
- 12 × 4 = 48.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 48 cm²
Worked Example 2
Problem: Find the area of a 10 cm by 5 cm rectangle.
- Use area = length × width.
- 10 × 5 = 50.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 50 cm²
Worked Example 3
Problem: Find the area of a 11 cm by 9 cm rectangle.
- Use area = length × width.
- 11 × 9 = 99.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 99 cm²
Worked Example 4
Problem: Find the area of a 3 cm by 9 cm rectangle.
- Use area = length × width.
- 3 × 9 = 27.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 27 cm²
Worked Example 5
Problem: Find the area of a 3 cm by 6 cm rectangle.
- Use area = length × width.
- 3 × 6 = 18.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 18 cm²
Worked Example 6
Problem: Find the area of a 5 cm by 7 cm rectangle.
- Use area = length × width.
- 5 × 7 = 35.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 35 cm²
Worked Example 7
Problem: Find the area of a 4 cm by 4 cm rectangle.
- Use area = length × width.
- 4 × 4 = 16.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 16 cm²
Worked Example 8
Problem: Find the area of a 11 cm by 9 cm rectangle.
- Use area = length × width.
- 11 × 9 = 99.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 99 cm²
Worked Example 9
Problem: Find the area of a 11 cm by 8 cm rectangle.
- Use area = length × width.
- 11 × 8 = 88.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 88 cm²
Worked Example 10
Problem: Find the area of a 11 cm by 7 cm rectangle.
- Use area = length × width.
- 11 × 7 = 77.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 77 cm²
Practice Exercise
Create and solve one new example of Opposite sides of a rectangle. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.4 Parallel sides
Parallel sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 4 and 11.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 2
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 9 and 2.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 3
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 4 and 11.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 4
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 13 and 13.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 5
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 7 and 20.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 6
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 19 and 4.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 7
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 11 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 8
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 20 and 3.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 9
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 11 and 11.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Worked Example 10
Problem: Create a simple Grade 4 example about Parallel sides using the numbers 8 and 19.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Parallel sides.
Practice Exercise
Create and solve one new example of Parallel sides. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.5 Perpendicular sides
Perpendicular sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 15 and 12.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 2
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 4 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 3
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 20 and 13.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 4
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 7 and 19.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 5
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 15 and 20.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 6
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 17 and 17.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 7
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 19 and 14.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 8
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 9 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 9
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 7 and 17.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Worked Example 10
Problem: Create a simple Grade 4 example about Perpendicular sides using the numbers 16 and 20.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Perpendicular sides.
Practice Exercise
Create and solve one new example of Perpendicular sides. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.6 Length and width
Metric measurement uses standard units. Choose a unit that matches the kind and size of the quantity. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Create a simple Grade 4 example about Length and width using the numbers 5 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 2
Problem: Create a simple Grade 4 example about Length and width using the numbers 5 and 19.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 3
Problem: Create a simple Grade 4 example about Length and width using the numbers 11 and 14.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 4
Problem: Create a simple Grade 4 example about Length and width using the numbers 7 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 5
Problem: Create a simple Grade 4 example about Length and width using the numbers 20 and 18.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 6
Problem: Create a simple Grade 4 example about Length and width using the numbers 15 and 17.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 7
Problem: Create a simple Grade 4 example about Length and width using the numbers 8 and 7.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 8
Problem: Create a simple Grade 4 example about Length and width using the numbers 6 and 13.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 9
Problem: Create a simple Grade 4 example about Length and width using the numbers 17 and 17.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Worked Example 10
Problem: Create a simple Grade 4 example about Length and width using the numbers 3 and 10.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Length and width.
Practice Exercise
Create and solve one new example of Length and width. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.7 Lines of symmetry
Lines of symmetry is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 15 and 19.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 2
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 5 and 12.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 3
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 10 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 4
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 16 and 11.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 5
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 5 and 14.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 6
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 9 and 17.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 7
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 10 and 19.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 8
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 15 and 4.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 9
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 16 and 12.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Worked Example 10
Problem: Create a simple Grade 4 example about Lines of symmetry using the numbers 12 and 8.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Lines of symmetry.
Practice Exercise
Create and solve one new example of Lines of symmetry. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.8 Squares as special rectangles
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Find the area of a 5 cm by 8 cm rectangle.
- Use area = length × width.
- 5 × 8 = 40.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 40 cm²
Worked Example 2
Problem: Find the area of a 6 cm by 7 cm rectangle.
- Use area = length × width.
- 6 × 7 = 42.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 42 cm²
Worked Example 3
Problem: Find the area of a 11 cm by 3 cm rectangle.
- Use area = length × width.
- 11 × 3 = 33.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 33 cm²
Worked Example 4
Problem: Find the area of a 6 cm by 6 cm rectangle.
- Use area = length × width.
- 6 × 6 = 36.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 36 cm²
Worked Example 5
Problem: Find the area of a 6 cm by 2 cm rectangle.
- Use area = length × width.
- 6 × 2 = 12.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 12 cm²
Worked Example 6
Problem: Find the area of a 11 cm by 9 cm rectangle.
- Use area = length × width.
- 11 × 9 = 99.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 99 cm²
Worked Example 7
Problem: Find the area of a 5 cm by 6 cm rectangle.
- Use area = length × width.
- 5 × 6 = 30.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 30 cm²
Worked Example 8
Problem: Find the area of a 11 cm by 3 cm rectangle.
- Use area = length × width.
- 11 × 3 = 33.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 33 cm²
Worked Example 9
Problem: Find the area of a 8 cm by 7 cm rectangle.
- Use area = length × width.
- 8 × 7 = 56.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 56 cm²
Worked Example 10
Problem: Find the area of a 5 cm by 5 cm rectangle.
- Use area = length × width.
- 5 × 5 = 25.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 25 cm²
Practice Exercise
Create and solve one new example of Squares as special rectangles. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.9 Classifying shapes using rectangle properties
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Find the area of a 7 cm by 3 cm rectangle.
- Use area = length × width.
- 7 × 3 = 21.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 21 cm²
Worked Example 2
Problem: Find the area of a 8 cm by 4 cm rectangle.
- Use area = length × width.
- 8 × 4 = 32.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 32 cm²
Worked Example 3
Problem: Find the area of a 8 cm by 7 cm rectangle.
- Use area = length × width.
- 8 × 7 = 56.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 56 cm²
Worked Example 4
Problem: Find the area of a 3 cm by 7 cm rectangle.
- Use area = length × width.
- 3 × 7 = 21.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 21 cm²
Worked Example 5
Problem: Find the area of a 8 cm by 2 cm rectangle.
- Use area = length × width.
- 8 × 2 = 16.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 16 cm²
Worked Example 6
Problem: Find the area of a 9 cm by 7 cm rectangle.
- Use area = length × width.
- 9 × 7 = 63.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 63 cm²
Worked Example 7
Problem: Find the area of a 8 cm by 2 cm rectangle.
- Use area = length × width.
- 8 × 2 = 16.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 16 cm²
Worked Example 8
Problem: Find the area of a 4 cm by 9 cm rectangle.
- Use area = length × width.
- 4 × 9 = 36.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 36 cm²
Worked Example 9
Problem: Find the area of a 4 cm by 3 cm rectangle.
- Use area = length × width.
- 4 × 3 = 12.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 12 cm²
Worked Example 10
Problem: Find the area of a 8 cm by 4 cm rectangle.
- Use area = length × width.
- 8 × 4 = 32.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 32 cm²
Practice Exercise
Create and solve one new example of Classifying shapes using rectangle properties. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.10 Finding missing properties
Finding missing properties is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 8 and 3.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 2
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 7 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 3
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 9 and 3.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 4
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 15 and 9.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 5
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 19 and 15.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 6
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 18 and 12.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 7
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 18 and 14.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 8
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 14 and 8.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 9
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 3 and 7.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Worked Example 10
Problem: Create a simple Grade 4 example about Finding missing properties using the numbers 9 and 2.
- Identify what the topic means.
- Use the numbers in a way that follows the rule.
- Check that the result or representation makes sense.
Very beginner explanation: Meaning comes first; the numbers should illustrate the concept clearly.
Answer: A correct example that demonstrates Finding missing properties.
Practice Exercise
Create and solve one new example of Finding missing properties. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.11 Drawing rectangles from clues
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Find the area of a 5 cm by 6 cm rectangle.
- Use area = length × width.
- 5 × 6 = 30.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 30 cm²
Worked Example 2
Problem: Find the area of a 9 cm by 4 cm rectangle.
- Use area = length × width.
- 9 × 4 = 36.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 36 cm²
Worked Example 3
Problem: Find the area of a 11 cm by 6 cm rectangle.
- Use area = length × width.
- 11 × 6 = 66.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 66 cm²
Worked Example 4
Problem: Find the area of a 6 cm by 7 cm rectangle.
- Use area = length × width.
- 6 × 7 = 42.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 42 cm²
Worked Example 5
Problem: Find the area of a 9 cm by 4 cm rectangle.
- Use area = length × width.
- 9 × 4 = 36.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 36 cm²
Worked Example 6
Problem: Find the area of a 9 cm by 5 cm rectangle.
- Use area = length × width.
- 9 × 5 = 45.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 45 cm²
Worked Example 7
Problem: Find the area of a 7 cm by 9 cm rectangle.
- Use area = length × width.
- 7 × 9 = 63.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 63 cm²
Worked Example 8
Problem: Find the area of a 5 cm by 4 cm rectangle.
- Use area = length × width.
- 5 × 4 = 20.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 20 cm²
Worked Example 9
Problem: Find the area of a 12 cm by 6 cm rectangle.
- Use area = length × width.
- 12 × 6 = 72.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 72 cm²
Worked Example 10
Problem: Find the area of a 7 cm by 3 cm rectangle.
- Use area = length × width.
- 7 × 3 = 21.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 21 cm²
Practice Exercise
Create and solve one new example of Drawing rectangles from clues. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
50.12 Rectangle properties in real objects
Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see. Work one step at a time, use a model or number sentence when useful, and check whether the answer is reasonable.
Beginner Explanation
First identify what is given and what must be found. Then choose a strategy, show the steps clearly, and check the final answer.
10 Worked Examples with Answers
Worked Example 1
Problem: Find the area of a 3 cm by 3 cm rectangle.
- Use area = length × width.
- 3 × 3 = 9.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 9 cm²
Worked Example 2
Problem: Find the area of a 9 cm by 2 cm rectangle.
- Use area = length × width.
- 9 × 2 = 18.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 18 cm²
Worked Example 3
Problem: Find the area of a 4 cm by 2 cm rectangle.
- Use area = length × width.
- 4 × 2 = 8.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 8 cm²
Worked Example 4
Problem: Find the area of a 7 cm by 9 cm rectangle.
- Use area = length × width.
- 7 × 9 = 63.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 63 cm²
Worked Example 5
Problem: Find the area of a 5 cm by 9 cm rectangle.
- Use area = length × width.
- 5 × 9 = 45.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 45 cm²
Worked Example 6
Problem: Find the area of a 10 cm by 2 cm rectangle.
- Use area = length × width.
- 10 × 2 = 20.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 20 cm²
Worked Example 7
Problem: Find the area of a 9 cm by 2 cm rectangle.
- Use area = length × width.
- 9 × 2 = 18.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 18 cm²
Worked Example 8
Problem: Find the area of a 11 cm by 5 cm rectangle.
- Use area = length × width.
- 11 × 5 = 55.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 55 cm²
Worked Example 9
Problem: Find the area of a 11 cm by 6 cm rectangle.
- Use area = length × width.
- 11 × 6 = 66.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 66 cm²
Worked Example 10
Problem: Find the area of a 5 cm by 8 cm rectangle.
- Use area = length × width.
- 5 × 8 = 40.
Very beginner explanation: Area measures the surface inside a 2D shape.
Answer: 40 cm²
Practice Exercise
Create and solve one new example of Rectangle properties in real objects. Show the steps and explain how you checked it.
Common Mistake
Do not rush into a calculation before understanding the question. Check place values, labels, units, and whether your answer fits the situation.
30 Review Questions and Answers
Q1. What is important to understand about Recognizing rectangles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q2. What is important to understand about Four right angles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q3. What is important to understand about Opposite sides of a rectangle?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q4. What is important to understand about Parallel sides?
Answer: Parallel sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q5. What is important to understand about Perpendicular sides?
Answer: Perpendicular sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q6. What is important to understand about Length and width?
Answer: Metric measurement uses standard units. Choose a unit that matches the kind and size of the quantity.
Q7. What is important to understand about Lines of symmetry?
Answer: Lines of symmetry is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q8. What is important to understand about Squares as special rectangles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q9. What is important to understand about Classifying shapes using rectangle properties?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q10. What is important to understand about Finding missing properties?
Answer: Finding missing properties is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q11. What is important to understand about Drawing rectangles from clues?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q12. What is important to understand about Rectangle properties in real objects?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q13. How would you explain Recognizing rectangles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q14. How would you explain Four right angles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q15. How would you explain Opposite sides of a rectangle?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q16. How would you explain Parallel sides?
Answer: Parallel sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q17. How would you explain Perpendicular sides?
Answer: Perpendicular sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q18. How would you explain Length and width?
Answer: Metric measurement uses standard units. Choose a unit that matches the kind and size of the quantity.
Q19. How would you explain Lines of symmetry?
Answer: Lines of symmetry is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q20. How would you explain Squares as special rectangles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q21. How would you explain Classifying shapes using rectangle properties?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q22. How would you explain Finding missing properties?
Answer: Finding missing properties is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q23. How would you explain Drawing rectangles from clues?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q24. How would you explain Rectangle properties in real objects?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q25. What should a beginner check when working with Recognizing rectangles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q26. What should a beginner check when working with Four right angles?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q27. What should a beginner check when working with Opposite sides of a rectangle?
Answer: Spatial reasoning uses shape, position, movement, and measurement. Diagrams, coordinates, and measurements make relationships easier to see.
Q28. What should a beginner check when working with Parallel sides?
Answer: Parallel sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q29. What should a beginner check when working with Perpendicular sides?
Answer: Perpendicular sides is an important Grade 4 mathematics idea in Rectangle Properties. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q30. What should a beginner check when working with Length and width?
Answer: Metric measurement uses standard units. Choose a unit that matches the kind and size of the quantity.