Numbers: An introduction to subtraction
Numbers: An introduction to subtraction

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Numbers: An introduction to subtraction

3 Subtraction rules – order matters

It’s important to remember that subtraction has different rules from addition.

For example, when you add up numbers, it doesn’t matter what order you add them up in. So 6 + 4 is exactly the same as 4 + 6. The result is 10 in both cases.

But in subtraction, order matters. So 6 – 4 is different from 4 – 6.

With the first, you start with 6, subtract 4, and are left with 2.

But with the second you start with 4 and if you subtract 6, which is a bigger number, you are 2 short, or minus 2.


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