Rounding and estimation

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# 1.2.2 Rounding to the nearest ten

The blouse in the figure above was £19 and you may well have thought of it as roughly £20. In this case you would be rounding to the nearest ten (pounds).

The rule for rounding to the nearest hundred can be adapted easily to rounding to the nearest ten. Instead of looking at the tens digit look at the units digit.

So £23 is rounded down (to £20) and £36 is rounded up (to £40).

## Example 1

The distance from London to Newcastle is 282 miles. Round this distance to the nearest 10 miles and the nearest hundred miles.

To round to the nearest 10, look at the units digit. This is a 2, so round down to 280 miles.

To round to the nearest 100, look at the tens digit. This is 8, so round up to 300 miles.

Therefore the distance from London to Newcastle is 280 miles, to the nearest ten miles, and 300 miles, to the nearest hundred miles.

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