Rounding is important because it makes numbers easier to manage and allows us to estimate answers.
Imagine you’re in a shop and you need to quickly estimate how much your shopping will be before you get to the till. You would round up the prices, like £1.90 to £2.00, to make it easier to add up.
The Rule for Rounding
Always look at the digit to the right of the one you’re supposed to be rounding to. For example, if you wanted to round to the nearest hundred, you would look at the tens column.
Rounding a price to the nearest pound is the same as rounding a decimal to the closest whole number.
If the price is £2.80, you can round up to £3 because the digit in the tenths position is 8. The closest whole number to 2.8 is 3.
If the price is £2.08, you can round down to £2 because the digit in the tenths position is 0. The closest whole number to 2.08 is 2.
Don't forget, if the digit you are rounding is 5, round up. £2.50 rounded to the nearest pound is £3.
Have a go at the activities and worksheets below:
Use a receipt, for example from the supermarket, and round all the prices up or down to the nearest pound.
Add all the rounded prices together to find an approximate cost.
How does this compare to the actual total cost on the receipt?
Click below for the worksheet (you do not need to print it). Answer in your exercise book.