In this activity, we will be rounding decimal numbers to the nearest whole number and then estimating the answer to a division.

For example:

Estimate the answer to this division by first rounding both decimals to the nearest whole numbers.

4.65 ÷ 1.3

A

÷

B

=

C

4.65 ÷ 1.3

5

÷

1

=

5

We need to remember our rules for rounding decimals to whole numbers for this activity!

If the number immediately after the decimal point, in the tenths column, is 5 or more, we round up the number in the ones column.

If the number in the tenths column is below 5, the number in the ones column will not change.

So, in the example above, 4.65 has a 6 in the tenths column, so it makes the 4 in the ones column round up to 5.

1.3 has a 3 in the tenths column, so it makes the number round down to 1.

Are you ready to get rounding?

Let's get started!