Chapter 4: Rounding and Estimation
Learn Grade 4 mathematics with very-beginner explanations, original worked examples, practice, reasoning, and review.
Chapter Overview
This chapter teaches Rounding and Estimation in original, simple language with step-by-step reasoning, worked examples, practice exercises, common mistakes, and review questions.
4.1 Why we round numbers
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 1,493 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,490
Worked Example 2
Problem: Round 6,048 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,050
Worked Example 3
Problem: Round 5,252 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 5,000
Worked Example 4
Problem: Round 4,426 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,400
Worked Example 5
Problem: Round 1,457 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,000
Worked Example 6
Problem: Round 724 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 720
Worked Example 7
Problem: Round 7,409 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,000
Worked Example 8
Problem: Round 6,483 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,500
Worked Example 9
Problem: Round 9,490 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,000
Worked Example 10
Problem: Round 7,285 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,000
Practice Exercise
Create and solve one new example of Why we round numbers. 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.
4.2 Rounding to the nearest ten
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 8,751 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,750
Worked Example 2
Problem: Round 4,599 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,600
Worked Example 3
Problem: Round 3,268 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 3,300
Worked Example 4
Problem: Round 6,099 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,000
Worked Example 5
Problem: Round 1,152 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,000
Worked Example 6
Problem: Round 4,559 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,600
Worked Example 7
Problem: Round 7,387 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,390
Worked Example 8
Problem: Round 1,830 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,830
Worked Example 9
Problem: Round 1,461 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,460
Worked Example 10
Problem: Round 4,283 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,280
Practice Exercise
Create and solve one new example of Rounding to the nearest ten. 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.
4.3 Rounding to the nearest hundred
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 6,920 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,920
Worked Example 2
Problem: Round 6,462 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,000
Worked Example 3
Problem: Round 2,110 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,000
Worked Example 4
Problem: Round 8,987 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,000
Worked Example 5
Problem: Round 4,800 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,800
Worked Example 6
Problem: Round 8,221 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,220
Worked Example 7
Problem: Round 5,577 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 5,600
Worked Example 8
Problem: Round 8,466 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,500
Worked Example 9
Problem: Round 3,929 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 3,900
Worked Example 10
Problem: Round 8,544 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,540
Practice Exercise
Create and solve one new example of Rounding to the nearest hundred. 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.
4.4 Rounding to the nearest thousand
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 1,158 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,200
Worked Example 2
Problem: Round 9,197 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,200
Worked Example 3
Problem: Round 8,688 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,700
Worked Example 4
Problem: Round 7,852 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,850
Worked Example 5
Problem: Round 7,858 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,900
Worked Example 6
Problem: Round 7,193 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,000
Worked Example 7
Problem: Round 1,791 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,000
Worked Example 8
Problem: Round 9,896 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,900
Worked Example 9
Problem: Round 9,884 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 10,000
Worked Example 10
Problem: Round 4,655 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 5,000
Practice Exercise
Create and solve one new example of Rounding to the nearest thousand. 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.
4.5 Using number lines to round
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 5,453 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 5,500
Worked Example 2
Problem: Round 2,800 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,800
Worked Example 3
Problem: Round 500 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 0
Worked Example 4
Problem: Round 4,745 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,700
Worked Example 5
Problem: Round 7,593 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,000
Worked Example 6
Problem: Round 2,426 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,000
Worked Example 7
Problem: Round 9,948 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,950
Worked Example 8
Problem: Round 6,575 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,600
Worked Example 9
Problem: Round 1,761 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,800
Worked Example 10
Problem: Round 1,483 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,480
Practice Exercise
Create and solve one new example of Using number lines to round. 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.
4.6 Finding two nearest benchmarks
Finding two nearest benchmarks is an important Grade 4 mathematics idea in Rounding and Estimation. 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 two nearest benchmarks using the numbers 17 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 Finding two nearest benchmarks.
Worked Example 2
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 10 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 two nearest benchmarks.
Worked Example 3
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 13 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 Finding two nearest benchmarks.
Worked Example 4
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 6 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 two nearest benchmarks.
Worked Example 5
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 14 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 Finding two nearest benchmarks.
Worked Example 6
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 7 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 two nearest benchmarks.
Worked Example 7
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks 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 Finding two nearest benchmarks.
Worked Example 8
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 2 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 Finding two nearest benchmarks.
Worked Example 9
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 20 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 two nearest benchmarks.
Worked Example 10
Problem: Create a simple Grade 4 example about Finding two nearest benchmarks using the numbers 4 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 Finding two nearest benchmarks.
Practice Exercise
Create and solve one new example of Finding two nearest benchmarks. 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.
4.7 Identifying a midpoint
Identifying a midpoint is an important Grade 4 mathematics idea in Rounding and Estimation. 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 Identifying a midpoint using the numbers 4 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 Identifying a midpoint.
Worked Example 2
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 12 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 Identifying a midpoint.
Worked Example 3
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 20 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 Identifying a midpoint.
Worked Example 4
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 14 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 Identifying a midpoint.
Worked Example 5
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 6 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 Identifying a midpoint.
Worked Example 6
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 19 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 Identifying a midpoint.
Worked Example 7
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 8 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 Identifying a midpoint.
Worked Example 8
Problem: Create a simple Grade 4 example about Identifying a midpoint 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 Identifying a midpoint.
Worked Example 9
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 16 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 Identifying a midpoint.
Worked Example 10
Problem: Create a simple Grade 4 example about Identifying a midpoint using the numbers 14 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 Identifying a midpoint.
Practice Exercise
Create and solve one new example of Identifying a midpoint. 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.
4.8 Rounding up and rounding down
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 4,009 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,010
Worked Example 2
Problem: Round 1,176 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,000
Worked Example 3
Problem: Round 1,800 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,800
Worked Example 4
Problem: Round 5,942 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,000
Worked Example 5
Problem: Round 2,611 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 3,000
Worked Example 6
Problem: Round 1,304 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,300
Worked Example 7
Problem: Round 2,388 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,000
Worked Example 8
Problem: Round 3,687 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,000
Worked Example 9
Problem: Round 6,839 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,840
Worked Example 10
Problem: Round 3,431 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 3,000
Practice Exercise
Create and solve one new example of Rounding up and rounding down. 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.
4.9 Choosing a useful rounding place
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 897 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 900
Worked Example 2
Problem: Round 9,837 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,800
Worked Example 3
Problem: Round 8,863 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,860
Worked Example 4
Problem: Round 9,159 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 9,200
Worked Example 5
Problem: Round 5,203 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 5,200
Worked Example 6
Problem: Round 5,766 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 5,800
Worked Example 7
Problem: Round 4,405 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,000
Worked Example 8
Problem: Round 2,108 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,100
Worked Example 9
Problem: Round 3,773 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 3,800
Worked Example 10
Problem: Round 7,461 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,000
Practice Exercise
Create and solve one new example of Choosing a useful rounding place. 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.
4.10 Estimating sums
Addition combines quantities. Align place values, regroup when needed, and estimate first to predict a reasonable answer. 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 Estimating sums using the numbers 20 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 Estimating sums.
Worked Example 2
Problem: Create a simple Grade 4 example about Estimating sums using the numbers 20 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 Estimating sums.
Worked Example 3
Problem: Create a simple Grade 4 example about Estimating sums using the numbers 17 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 Estimating sums.
Worked Example 4
Problem: Create a simple Grade 4 example about Estimating sums 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 Estimating sums.
Worked Example 5
Problem: Create a simple Grade 4 example about Estimating sums 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 Estimating sums.
Worked Example 6
Problem: Create a simple Grade 4 example about Estimating sums using the numbers 10 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 Estimating sums.
Worked Example 7
Problem: Create a simple Grade 4 example about Estimating sums 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 Estimating sums.
Worked Example 8
Problem: Create a simple Grade 4 example about Estimating sums 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 Estimating sums.
Worked Example 9
Problem: Create a simple Grade 4 example about Estimating sums using the numbers 7 and 16.
- 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 Estimating sums.
Worked Example 10
Problem: Create a simple Grade 4 example about Estimating sums using the numbers 7 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 Estimating sums.
Practice Exercise
Create and solve one new example of Estimating sums. 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.
4.11 Estimating differences
Subtraction finds what remains or the difference between quantities. Addition is a useful way to check. 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 Estimating differences using the numbers 6 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 Estimating differences.
Worked Example 2
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 20 and 6.
- 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 Estimating differences.
Worked Example 3
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 3 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 Estimating differences.
Worked Example 4
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 4 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 Estimating differences.
Worked Example 5
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 6 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 Estimating differences.
Worked Example 6
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 2 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 Estimating differences.
Worked Example 7
Problem: Create a simple Grade 4 example about Estimating differences 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 Estimating differences.
Worked Example 8
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 15 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 Estimating differences.
Worked Example 9
Problem: Create a simple Grade 4 example about Estimating differences using the numbers 9 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 Estimating differences.
Worked Example 10
Problem: Create a simple Grade 4 example about Estimating differences 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 Estimating differences.
Practice Exercise
Create and solve one new example of Estimating differences. 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.
4.12 Checking whether an estimate is reasonable
Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original 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: Round 6,222 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 6,000
Worked Example 2
Problem: Round 1,708 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 2,000
Worked Example 3
Problem: Round 6,890 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,000
Worked Example 4
Problem: Round 4,393 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 4,400
Worked Example 5
Problem: Round 478 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 500
Worked Example 6
Problem: Round 7,497 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,500
Worked Example 7
Problem: Round 7,064 to the nearest 10.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 7,060
Worked Example 8
Problem: Round 601 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 1,000
Worked Example 9
Problem: Round 7,686 to the nearest 1,000.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,000
Worked Example 10
Problem: Round 8,237 to the nearest 100.
- Find the rounding place.
- Look one place to the right.
- 0–4 stays; 5–9 rounds up.
Very beginner explanation: Rounding creates a nearby benchmark.
Answer: 8,200
Practice Exercise
Create and solve one new example of Checking whether an estimate is reasonable. 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 Why we round numbers?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q2. What is important to understand about Rounding to the nearest ten?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q3. What is important to understand about Rounding to the nearest hundred?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q4. What is important to understand about Rounding to the nearest thousand?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q5. What is important to understand about Using number lines to round?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q6. What is important to understand about Finding two nearest benchmarks?
Answer: Finding two nearest benchmarks is an important Grade 4 mathematics idea in Rounding and Estimation. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q7. What is important to understand about Identifying a midpoint?
Answer: Identifying a midpoint is an important Grade 4 mathematics idea in Rounding and Estimation. 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 Rounding up and rounding down?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q9. What is important to understand about Choosing a useful rounding place?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q10. What is important to understand about Estimating sums?
Answer: Addition combines quantities. Align place values, regroup when needed, and estimate first to predict a reasonable answer.
Q11. What is important to understand about Estimating differences?
Answer: Subtraction finds what remains or the difference between quantities. Addition is a useful way to check.
Q12. What is important to understand about Checking whether an estimate is reasonable?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q13. How would you explain Why we round numbers?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q14. How would you explain Rounding to the nearest ten?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q15. How would you explain Rounding to the nearest hundred?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q16. How would you explain Rounding to the nearest thousand?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q17. How would you explain Using number lines to round?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q18. How would you explain Finding two nearest benchmarks?
Answer: Finding two nearest benchmarks is an important Grade 4 mathematics idea in Rounding and Estimation. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q19. How would you explain Identifying a midpoint?
Answer: Identifying a midpoint is an important Grade 4 mathematics idea in Rounding and Estimation. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.
Q20. How would you explain Rounding up and rounding down?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q21. How would you explain Choosing a useful rounding place?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q22. How would you explain Estimating sums?
Answer: Addition combines quantities. Align place values, regroup when needed, and estimate first to predict a reasonable answer.
Q23. How would you explain Estimating differences?
Answer: Subtraction finds what remains or the difference between quantities. Addition is a useful way to check.
Q24. How would you explain Checking whether an estimate is reasonable?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q25. What should a beginner check when working with Why we round numbers?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q26. What should a beginner check when working with Rounding to the nearest ten?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q27. What should a beginner check when working with Rounding to the nearest hundred?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q28. What should a beginner check when working with Rounding to the nearest thousand?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q29. What should a beginner check when working with Using number lines to round?
Answer: Rounding replaces a number with a nearby benchmark to make estimation easier. The estimate should stay close to the original quantity.
Q30. What should a beginner check when working with Finding two nearest benchmarks?
Answer: Finding two nearest benchmarks is an important Grade 4 mathematics idea in Rounding and Estimation. Understand the meaning first, then use a clear representation or strategy and check whether the answer makes sense.