Addition and Subtraction Worksheets for Grade 1 with Answer Key - Free Printable

Let's solve each problem step by step on the Addition and Subtraction Practice Worksheet.

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Problems 1 to 15 (Vertical Format)

We'll go through each one:

1. 5 + 3 = 8
2. 8 - 7 = 1
3. 2 + 2 = 4
4. 4 + 4 = 8
5. 3 + 9 = 12
6. 3 - 1 = 2
7. 0 + 7 = 7
8. 4 + 5 = 9
9. 6 + 6 = 12
10. 9 - 7 = 2
11. 8 - 3 = 5
12. 4 + 3 = 7
13. 4 + 7 = 11
14. 2 - 1 = 1
15. 7 - 0 = 7

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Problems 15 to 20 (Horizontal Format)

Note: Problem #15 is listed twice — once as vertical, once as horizontal. Let's assume it's a typo and proceed with the horizontal ones starting from #15.

15. 7 + 7 = 14
16. 9 - 1 = 8
17. 8 + 3 = 11
18. 4 + 3 = 7
19. 6 - 2 = 4
20. 5 + 2 = 7

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✔ Final Answers:

| Problem | Answer |
|--------|--------|
| 1 | 8 |
| 2 | 1 |
| 3 | 4 |
| 4 | 8 |
| 5 | 12 |
| 6 | 2 |
| 7 | 7 |
| 8 | 9 |
| 9 | 12 |
| 10 | 2 |
| 11 | 5 |
| 12 | 7 |
| 13 | 11 |
| 14 | 1 |
| 15 | 7 |
| 15 | 14 |
| 16 | 8 |
| 17 | 11 |
| 18 | 7 |
| 19 | 4 |
| 20 | 7 |

> ⚠️ Note: There’s a duplicate problem number (#15) — the first #15 is vertical (7 - 0 = 7), and the second #15 is horizontal (7 + 7 = 14). This might be a formatting error in the worksheet.

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✔ Corrected List (with unique numbers):

| Number | Problem | Answer |
|--------|---------------|--------|
| 1 | 5 + 3 | 8 |
| 2 | 8 - 7 | 1 |
| 3 | 2 + 2 | 4 |
| 4 | 4 + 4 | 8 |
| 5 | 3 + 9 | 12 |
| 6 | 3 - 1 | 2 |
| 7 | 0 + 7 | 7 |
| 8 | 4 + 5 | 9 |
| 9 | 6 + 6 | 12 |
| 10 | 9 - 7 | 2 |
| 11 | 8 - 3 | 5 |
| 12 | 4 + 3 | 7 |
| 13 | 4 + 7 | 11 |
| 14 | 2 - 1 | 1 |
| 15 | 7 - 0 | 7 |
| 16 | 7 + 7 | 14 |
| 17 | 9 - 1 | 8 |
| 18 | 8 + 3 | 11 |
| 19 | 4 + 3 | 7 |
| 20 | 6 - 2 | 4 |
| 21 | 5 + 2 | 7 |

Wait! The original worksheet labels the last five problems as 15 to 20, but we already used 15 for the vertical problem.

So, likely, the horizontal problems are numbered 15–20, and the earlier vertical problems are 1–15.

But there's an overlap: both vertical #15 and horizontal #15 exist.

Let’s re-express the full list clearly based on the layout:

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✔ Correct Interpretation:

The worksheet has:

- Vertical Problems: ① to ⑮ (15 problems)
- Then Horizontal Problems: ⑮ to ⑳ (but labeled as 15 to 20)

So problem #15 appears twice — this is a numbering mistake.

Let’s fix it:

#### Vertical Problems (① to ⑮):
1. 5 + 3 = 8
2. 8 - 7 = 1
3. 2 + 2 = 4
4. 4 + 4 = 8
5. 3 + 9 = 12
6. 3 - 1 = 2
7. 0 + 7 = 7
8. 4 + 5 = 9
9. 6 + 6 = 12
10. 9 - 7 = 2
11. 8 - 3 = 5
12. 4 + 3 = 7
13. 4 + 7 = 11
14. 2 - 1 = 1
15. 7 - 0 = 7

Then:

#### Horizontal Problems (labeled 15 to 20):
15. 7 + 7 = 14 ← This should probably be #16
16. 9 - 1 = 8 ← Should be #17
17. 8 + 3 = 11 ← Should be #18
18. 4 + 3 = 7 ← Should be #19
19. 6 - 2 = 4 ← Should be #20
20. 5 + 2 = 7 ← Should be #21

But since they're labeled 15–20, we’ll keep that.

So final answers as per the worksheet labels:

| Number | Problem | Answer |
|--------|----------------|--------|
| 1 | 5 + 3 | 8 |
| 2 | 8 - 7 | 1 |
| 3 | 2 + 2 | 4 |
| 4 | 4 + 4 | 8 |
| 5 | 3 + 9 | 12 |
| 6 | 3 - 1 | 2 |
| 7 | 0 + 7 | 7 |
| 8 | 4 + 5 | 9 |
| 9 | 6 + 6 | 12 |
| 10 | 9 - 7 | 2 |
| 11 | 8 - 3 | 5 |
| 12 | 4 + 3 | 7 |
| 13 | 4 + 7 | 11 |
| 14 | 2 - 1 | 1 |
| 15 | 7 - 0 | 7 |
| 15 | 7 + 7 = ______ | 14 |
| 16 | 9 - 1 = ______ | 8 |
| 17 | 8 + 3 = ______ | 11 |
| 18 | 4 + 3 = ______ | 7 |
| 19 | 6 - 2 = ______ | 4 |
| 20 | 5 + 2 = ______ | 7 |

> 🟨 Note: The two problems labeled #15 suggest a typo. One should be #16 or higher.

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✔ Final Answer Key (by label):

| Problem | Answer |
|--------|--------|
| 1 | 8 |
| 2 | 1 |
| 3 | 4 |
| 4 | 8 |
| 5 | 12 |
| 6 | 2 |
| 7 | 7 |
| 8 | 9 |
| 9 | 12 |
| 10 | 2 |
| 11 | 5 |
| 12 | 7 |
| 13 | 11 |
| 14 | 1 |
| 15 | 7 |
| 15 | 14 |
| 16 | 8 |
| 17 | 11 |
| 18 | 7 |
| 19 | 4 |
| 20 | 7 |

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✔ Summary of All Answers:

1. 8
2. 1
3. 4
4. 8
5. 12
6. 2
7. 7
8. 9
9. 12
10. 2
11. 5
12. 7
13. 11
14. 1
15. 7
15. 14
16. 8
17. 11
18. 7
19. 4
20. 7

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✔ Final Score: If all answers are correct, the student gets 20 points (assuming 1 point per problem).

Let me know if you'd like a printable version or explanation for any specific problem!