Easy subtraction uses either of two carrying and borrowing methods. You should recognise one or even
both methods.
The difference between standard subtraction and easy subtraction is minor, but important. I will
explain easy subtraction with two methods of carrying and borrowing. Use the method you are familiar
with or that you find easier.
Subtraction method one
Here is a typical subtraction:
This is how the working might look:Let’s see how easy subtraction works. Subtract 7 from 5. You can’t, so you ‘borrow’ 1 from the tens
column. Cross out the 6 and write 5. Now, here is the difference. You don’t say 7 from 15, you say 7
from 10 equals 3, then add the number above (5) to get 8, the first digit of the answer.
With this method, you never subtract from any number higher than 10. The rest is addition.
Nine from 5 won’t go, so borrow again. Nine from 10 is 1, plus 5 is 6, the next digit of the answer.
Eight from 1 won’t go, so borrow again. Eight from 10 is 2, plus 1 is 3, the next digit of the answer.
Three from 7 is 4, the final digit of the answer.
Subtraction method two
Subtract 7 from 5. You can’t, so you borrow 1 from the tens column. Put a 1 in front of the 5 to make
15 and write a small 1 alongside the 9 in the tens column. Using our easy method, you don’t say 7 from
15, but 7 from 10 is 3, plus 5 on top gives 8, the first digit of the answer.
Ten (9 plus 1 carried) from 6 won’t go, so we have to borrow; 10 from 10 is 0, plus 6 is 6.
Nine from 2 won’t go, so we borrow again. Nine from 10 is 1, plus 2 is 3.
Four from 8 is 4. We have our answer.
You don’t have to learn or know the combinations of single-digit numbers that add to more than 10.
You never subtract from any number higher than 10. Most of the calculation is addition. This makes the
calculations easier and reduces mistakes.
Test yourself
Try these for yourself:a) b)
The answers are:
a) 2,757
b) 2,238