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
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.
Image caption, Number line calculation
Calculate 4 - 5 - 3
1 of 4
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