Adding and subtracting positive numbers

To add and subtract numbers always begin counting from zero.

When adding positive numbers, count to the right.

When subtracting positive numbers, count to the left.

Using a number line

Number line showing negative and positive numbers

Example

Calculate 4 - 5 - 3.

Imagine moving up and down a number line to get to the answer.

Starting from 0:

  • count up to 4
  • then subtract 5
  • then subtract 3

The answer is -4.

Number line showing negative and positive numbers

Number line calculation

Calculate 4 - 5 - 3

curriculum-key-fact
  • When adding positive numbers, count to the right.
  • When subtracting positive numbers, count to the left.