Arithmetic Grade Three

Lesson Thirty-six: Subtraction

Review this example:

To subtract bigger numbers you follow the same steps as with smaller numbers, you just have more columns to deal with. Consider this example: 


    342
   - 55
  -------
Notice that both the numbers in the tens and the ones column need to borrow. In this problem we will first need to borrow one from the hundreds column for the tens column and then borrow one from the tens column for the ones column. Once we deal with the borrowing we can just subtract like normal.

Here's the problem done step-by-step.
ORIGINAL PROBLEM
STEP ONE: Borrow one from the hundreds and adjust the tens
STEP TWO: Borrow one from the tens column and adjust the ones
STEP THREE: Subtract the ones column.
STEP FOUR: Subtract the tens column.
STEP FIVE: Bring down the number in the hundreds column.

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