With written subtraction, you calculate column by column from right to left.
The ones are under the ones, the tens under the tens, the hundreds under the hundreds.
Here is how you do it:
1. First subtract the ones.
2. If the top digit is not enough, you regroup and take 1 from the next place value.
3. Then subtract the tens and finally the hundreds.
Tip: When regrouping, you take a ten or a hundred and note it in the small boxes.
Example: 543 − 218
Ones: 3 − 8 is not possible. You regroup one ten: 13 − 8 = 5.
Tens: One of the 4 tens is gone, so 3 − 1 = 2.
Hundreds: 5 − 2 = 3.
Result: 325
The numbers filled in show the solution.
Example
For parents
What does this exercise practice?
This exercise trains place-value understanding and regrouping when subtracting large numbers.
Common pitfalls
Children often subtract the smaller digit from the bigger one, no matter where it stands. Always write down the regrouping!
How to practice at home
While shopping, calculate the change and check the result using the written method.
Related: Written Addition, Inverse Operations