Adding 10ths and 100ths worksheet with 20 fraction addition problems and answers.

Let’s solve each problem step by step. We’re adding fractions with denominators of 10 and 100. To add them, we need to make the denominators the same — usually convert the tenths (denominator 10) into hundredths (denominator 100).

Remember:
To convert a fraction with denominator 10 to denominator 100, multiply numerator and denominator by 10.
Example: 3/10 = 30/100

Then just add the numerators. Denominator stays 100.

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Problem 1:
4/100 + 8/10
→ 8/10 = 80/100
→ 4/100 + 80/100 = 84/100

Problem 2:
11/100 + 6/10
→ 6/10 = 60/100
→ 11/100 + 60/100 = 71/100

Problem 3:
12/100 + 2/10
→ 2/10 = 20/100
→ 12/100 + 20/100 = 32/100

Problem 4:
63/100 + 1/10
→ 1/10 = 10/100
→ 63/100 + 10/100 = 73/100

Problem 5:
2/10 + 78/100
→ 2/10 = 20/100
→ 20/100 + 78/100 = 98/100

Problem 6:
3/10 + 51/100
→ 3/10 = 30/100
→ 30/100 + 51/100 = 81/100

Problem 7:
3/10 + 61/100
→ 3/10 = 30/100
→ 30/100 + 61/100 = 91/100

Problem 8:
11/100 + 8/10
→ 8/10 = 80/100
→ 11/100 + 80/100 = 91/100

Problem 9:
1/100 + 4/10
→ 4/10 = 40/100
→ 1/100 + 40/100 = 41/100

Problem 10:
4/10 + 47/100
→ 4/10 = 40/100
→ 40/100 + 47/100 = 87/100

Problem 11:
21/100 + 6/10
→ 6/10 = 60/100
→ 21/100 + 60/100 = 81/100

Problem 12:
5/10 + 38/100
→ 5/10 = 50/100
→ 50/100 + 38/100 = 88/100

Problem 13:
7/10 + 18/100
→ 7/10 = 70/100
→ 70/100 + 18/100 = 88/100

Problem 14:
3/10 + 33/100
→ 3/10 = 30/100
→ 30/100 + 33/100 = 63/100

Problem 15:
2/100 + 3/10
→ 3/10 = 30/100
→ 2/100 + 30/100 = 32/100

Problem 16:
6/10 + 33/100
→ 6/10 = 60/100
→ 60/100 + 33/100 = 93/100

Problem 17:
8/100 + 5/10
→ 5/10 = 50/100
→ 8/100 + 50/100 = 58/100

Problem 18:
4/10 + 32/100
→ 4/10 = 40/100
→ 40/100 + 32/100 = 72/100

Problem 19:
5/10 + 28/100
→ 5/10 = 50/100
→ 50/100 + 28/100 = 78/100

Problem 20:
15/100 + 4/10
→ 4/10 = 40/100
→ 15/100 + 40/100 = 55/100

All answers match the provided answer key. No errors found.

Final Answer:
1. 84/100
2. 71/100
3. 32/100
4. 73/100
5. 98/100
6. 81/100
7. 91/100
8. 91/100
9. 41/100
10. 87/100
11. 81/100
12. 88/100
13. 88/100
14. 63/100
15. 32/100
16. 93/100
17. 58/100
18. 72/100
19. 78/100
20. 55/100