Fractions are easier to multiply than decimals (without the calculator). So if we want to multiply a decimal by a whole number, we can just write the decimal as a fraction, multiply it, and then rewrite it as a decimal.

Worked Examples

(a) 0.03 x 5

(b) 0.002 x 4

Exercise 1

Alternative method

Although this method will always work, with some harder calculations it is often easier to look at the original calculation to get an idea of how large the answer should be, then do the multiplication ignoring any decimal points and write the answer, putting the decimal point where it should be based on the initial estimation.

Worked example

Work out 12.43 x 5

Exercise 2

Dividing Decimals

Division of decimal numbers by whole numbers follows the same process that we use when dividing whole numbers by whole numbers

Worked Example

Calculate 5.4 ÷ 4

Exercise 3

Answers to all three exercises