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# Subtraction as difference

Difference is a comparison between two or more sets.

For example, if a set of 8 is compared with a set of 5, there is a difference of 3 objects between the sets.

This may be recorded as 5 + 3 = 8 or 8 – 5 = 3 where 3 is the difference.

In mental calculation it is often easier to regard a take away subtraction context as finding a difference. Adding on to solve the problem is frequently easier.

For example, 203 – 188 = ? is easier to solve as 188 + ? = 203.

Finding difference is contextually more difficult than taking away as the situation does not suggest a physical action to solve it.

You can read more about inverse operations.

## Differences

Finding the difference between two quantities is a common type of calculation. Difference problems can be solved using either subtraction or adding on from the smaller number.

## Equal differences

Difference problems can be made easier by adjusting both numbers by the same amount.