Subtraction — Chapter Summary

Subtraction means taking away one number

Subtraction means taking away one number from another. For example, if you have 8 apples and eat 3, you are left with 5. This is written as 8 – 3 = 5.

When the top digit is bigger

When the top digit is bigger than the bottom digit in each column (ones, tens, hundreds), we can subtract directly. For example, in 67 – 25, we subtra

When the top digit is smaller

When the top digit is smaller than the bottom digit, we borrow 1 from the next higher place. For example, in 50 – 24, we cannot subtract 4 from 0, so

Subtracting 0 from any number gives

Subtracting 0 from any number gives the same number. For example, 45 – 0 = 45. Subtracting 1 gives the previous number (predecessor), like 64 – 1 = 63