Understanding Subtraction

How do you subtract whole numbers?

First, remember this:

  • When subtracting whole numbers, always work from right to left, and always subtract the bottom number from the top number. Subtract the digits in the ones column first, and then subtract the digits in the tens column.

Example 1: First subtract the digits in the ones column. Use the blocks beside the problem to help you understand.

  Now subtract the digits in the tens column
(8 tens – 0 tens = 8 tens).


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