# Rounding to estimate

## Lesson details

### Key learning points

1. In this lesson, we will apply our understanding of rounding to the nearest multiples of 10 000 and 1000 to estimate the answer to addition equations.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

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## Worksheet

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## Starter quiz

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### 5 Questions

Q1.
Which equation demonstrates how the number 346 000 can be partitioned?
30 000 + 4000 + 600
300 + 40 + 6
Correct answer: 300 000 + 40 000 + 6000
3000 + 400 + 60
Q2.
2. Use partitioning to solve the equation: 723 000 + 15 000 =
728 000
748 000
758 000
Q3.
3. Use partitioning to solve the equation: 456 000 - 132 000 =
234 000
235 000
325 000
Q4.
4. Use partitioning to solve the equation: 158 000 + 26 000 =
164 000
174 000
178 000
Q5.
5. Use partitioning to solve the equation: 738 000 - 156 000 =
482 000
682 000
782 000

## Exit quiz

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### 5 Questions

Q1.
What does 'rounding to estimate' mean?
Adding and subtracting using the column method.
Correct answer: Rounding numbers in an equation to provide an approximate answer before calculation.
Using decimal numbers in addition equations.
Using whole numbers in addition equations.
Q2.
Round '456 244' to the nearest multiple of 10 000.
400 000
450 000
500 000
Q3.
3. Using rounding to the nearest multiple of 10 000 to estimate the answer to: 341 782 + 456 913 =
300 000 + 500 000 = 800 000
340 000 + 450 000 = 790 000
Correct answer: 340 000 + 460 000 = 800 000
342 000 + 457 000 = 799 000
Q4.
4. Use rounding to the nearest multiple of 1000 to estimate the answer to: 187 221 + 243 891 =
187 000 + 243 000 = 430 000
Correct answer: 187 000 + 244 000 = 431 000
190 000 + 240 000 = 430 000
200 000 + 200 000 = 400 000
Q5.
What is one of the problems associated with rounding to estimate?
Rounding to estimate always takes much longer than actually calculating the answer.