When we double a number we add it to itself, or just multiply it by 2

This is also called finding twice the number.

Examples

Double 4 is

4 + 4 or 2 × 4 = 8

Twice 9 is

9 + 9 or 2 × 9 = 18

Lots of different ways of saying  a calculation, but all meaning the same thing! Confusing, isn't it?

Don't worry - it will get easier the more you practise, so let's get started now!