Year 8 Adding and Subtracting Decimals Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 8 decimals worksheet.
Year 8 Adding and Subtracting Decimals Worksheet — Level 1 — Answers
Line up the decimal points before you add or subtract.
1.
39.4
−2.1
Answer: 37.3
- Line up the decimal points
- 39.4 − 2.1 = 37.3
2.
19.2
−15.0
Answer: 4.2
- Line up the decimal points
- 19.2 − 15.0 = 4.2
3.
6.3
−4.3
Answer: 2.0
- Line up the decimal points
- 6.3 − 4.3 = 2.0
4.
23.6
−19.4
Answer: 4.2
- Line up the decimal points
- 23.6 − 19.4 = 4.2
5.
10.8
+10.7
Answer: 21.5
- Line up the decimal points
- 10.8 + 10.7 = 21.5
6.
19.8
+33.9
Answer: 53.7
- Line up the decimal points
- 19.8 + 33.9 = 53.7
7.
34.5
+26.4
Answer: 60.9
- Line up the decimal points
- 34.5 + 26.4 = 60.9
8.
36.2
+34.1
Answer: 70.3
- Line up the decimal points
- 36.2 + 34.1 = 70.3
9.
39.7
−15.9
Answer: 23.8
- Line up the decimal points
- 39.7 − 15.9 = 23.8
10.
13.1
−6.5
Answer: 6.6
- Line up the decimal points
- 13.1 − 6.5 = 6.6
11.
35.6
−16.6
Answer: 19.0
- Line up the decimal points
- 35.6 − 16.6 = 19.0
12.
47.5
+21.8
Answer: 69.3
- Line up the decimal points
- 47.5 + 21.8 = 69.3
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.