6 Subtracting when you have to borrow
If the digit at the top of any column in your subtraction is smaller than the digit at the bottom of the same column, you need to borrow (or carry) from the next column on the left.
There is an example of this below. Click on each step in turn to see how to carry out the calculation.
Click on ‘Now read the discussion’ to see all the individual steps at once.
In this example you borrowed once. But sometimes you need to borrow in more than one column. Whichever column you are in, you do this in the same way, by borrowing 1 from the column to the left.