FRACTIONS, DECIMALS AND PERCENTAGES

Adding Decimals

Learn the reliable method for adding decimals, then apply it to 11+ exam-style questions.

1 · WHAT YOU NEED TO KNOW

The idea

Decimal addition and subtraction depend on keeping equal place values in the same column.

Picture itSee each decimal digit hold its place
Stationery and UK money arranged as a real-life shopping problem
2 · THE METHOD

Follow these steps

  1. Align the decimal points.
  2. Add zero placeholders where useful.
  3. Calculate column by column and place the decimal point in line.
3 · WORKED EXAMPLES

See the method in action

Example 1

A jug contains 3.98 litres. 2.71 litres and 0.65 litres are added. How much is in the jug now?

  1. Write all three measurements with aligned decimal points and add them.
Answer: 7.34 litres
Example 2

A route has stages of 3.31 km, 1.58 km and 0.99 km. The full route is 7.13 km. How far remains?

  1. Add the completed stages, then subtract that total from 7.13 km.
Answer: 1.25 km
4 · ELEVENSPRINT TIP

A useful shortcut

Calculate column by column and place the decimal point in line.

5 · COMMON MISTAKES

Watch out for these

6 · TRY IT YOURSELF

Three fresh questions

Ready to check the method? You will get three fresh, validated questions.