Subtraction Within 20: Worksheet #1
A gentle mixed set: this subtraction within 20 worksheet has thirty problems for ages 6-7, and only two of them ask the child to cross ten.
2 A4 pages · for home and classroom use
Labugen
Subtraction up to 20
set no. 105
- 1.6 - 1 =
- 2.5 - 3 =
- 3.18 - 5 =
- 4.17 - 3 =
- 5.19 - 8 =
- 6.2 - 1 =
- 7.19 - 16 =
- 8.14 - 3 =
- 9.8 - 5 =
- 10.6 - 3 =
- 11.18 - 10 =
- 12.9 - 4 =
- 13.3 - 1 =
- 14.6 - 5 =
- 15.6 - 2 =
- 16.13 - 11 =
- 17.8 - 6 =
- 18.11 - 4 =
- 19.18 - 11 =
- 20.8 - 7 =
- 21.4 - 3 =
- 22.5 - 4 =
- 23.8 - 2 =
- 24.15 - 6 =
- 25.5 - 1 =
- 26.4 - 2 =
- 27.16 - 6 =
- 28.9 - 6 =
- 29.18 - 1 =
- 30.19 - 3 =
How to use this worksheet
- Look at problems 11 and 27 first: 18 − 10 and 16 − 6. Ask what happens when you take away the whole ten, or all the ones.
- Solve the rest in order. Problems like 17 − 3 or 19 − 8 are done by subtracting the ones and keeping the ten.
- Leave 11 − 4 and 15 − 6 for last: these two cross ten and deserve a slower look.
- Check with the answer page and tick each correct problem.
What this worksheet teaches
The page mixes small facts within 10 (seventeen problems such as 6 − 1 and 8 − 5) with teen numbers (18 − 5, 19 − 3), and twenty-four of the thirty answers are 10 or less. It trains children to look at a problem before calculating: is it a quick fact, a ones-only step or a real crossing of ten? Four problems take a two-digit number from a teen number (19 − 16, 18 − 10, 13 − 11 and 18 − 11), which prepares children for subtracting tens and ones separately.
Count up when the numbers are close
When the numbers are close, counting up beats taking away. For 19 − 16, start at 16 and count "17, 18, 19": three steps, so the answer is 3. The same works for 13 − 11 (2) and 18 − 11 (7).