Subtraction Within 100: Worksheet #1
Some problems need borrowing and some do not: this subtraction within 100 worksheet mixes both in forty column problems, so children aged 7-8 learn to decide before they calculate.
2 A4 pages · for home and classroom use
Labugen
Subtraction up to 100
set no. 203
- 74-15
- 24-5
- 19-8
- 42-10
- 18-9
- 40-39
- 35-14
- 19-5
- 66-15
- 15-5
- 23-22
- 40-3
- 44-39
- 51-2
- 65-39
- 64-17
- 49-18
- 69-42
- 3-2
- 32-27
- 89-73
- 39-27
- 8-2
- 11-6
- 20-11
- 82-49
- 68-52
- 41-11
- 71-24
- 43-28
- 12-6
- 47-15
- 43-40
- 41-33
- 29-1
- 66-60
- 100-75
- 76-4
- 29-6
- 77-29
How to use this worksheet
- Before solving each problem, compare the ones digits: if the top one is smaller, as in 74 − 15, borrowing is needed.
- Let your child put a small dot next to every problem that needs borrowing; nineteen of the forty do.
- Check a row at a time with the answer key, counting across the rows of five.
What this worksheet teaches
The page mixes nineteen problems with borrowing (74 − 15, 65 − 39, 82 − 49) and twenty-one without it (66 − 15, 89 − 73, 49 − 18). Answers range from 1 to 72. A few surprises keep attention up: 100 − 75 has a three-digit top number, and 40 − 39, 23 − 22 and 3 − 2 all give 1. Deciding whether to regroup is a separate skill from regrouping itself, and mixed pages like this one practice exactly that.
Borrow or not? Look at the ones first
In column subtraction, borrowing means breaking one ten into ten ones. In 74 − 15, 4 ones are not enough to take away 5, so one of the 7 tens becomes 10 ones: 14 − 5 = 9 and 6 − 1 = 5, giving 59. In 66 − 15 the ones are fine (6 − 5), so nothing changes. Checking with addition closes the loop: 59 + 15 = 74.