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Watch: How to round numbers

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Rounding to the nearest 10

To round a number to the nearest 10, look at the units digit.

If the units digit is 5 or more, round up. If the units digit is 4 or less, round down.

The last digit in 356 is 6. So we round it up to 360.

356 鈫 360

The last digit of 352 is 2. So we round it down to 350.

352 鈫 350

475 ends in a 5. We always round a 5 up. So 475 rounds up to 480.

475 鈫 480

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Rounding to the nearest 100

To round a number to the nearest 100, look at the tens digit. If the tens digit is 5 or more, round up. If the tens digit is 4 or less, round down.

The tens digit in 3281 is 8. So we round it up to 3300.

3281 鈫 3300

The tens digit of 3216 is 1. So we round it down to 3200.

3216 鈫 3200

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Rounding to the nearest 1000

To round a number to the nearest 1000, look at the hundreds digit. If the hundreds digit is 5 or more, round up. If the hundreds digit is 4 or less, round down.

The hundreds digit in 4559 is 5. So we round it up to 5000.

4559 鈫 5000

The hundreds digit of 4295 is 2. So we round it down to 4000.

4295 鈫 4000

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Activity 1

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Activity 2

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Quiz

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Teaching resources

Looking for other ways to bring the magic of maths to your classroom? This short animated film is from the 91热爆 Teach Series, Hypatia's Mathematical Maze, and dives into how and why we round numbers.

91热爆 Teach has thousands of free, curriculum-linked resources to help deliver lessons - all arranged by subject and age group.

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More on Rounding and estimating

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