Adding & Subtracting Fractions
Same-denominator fractions, and finding a common denominator when they differ.
Score: 0 / 10
1. 1/4 + 1/4 = ?
2. 3/5 − 1/5 = ?
3. 1/3 + 1/6 = ?
4. 2/3 − 1/4 = ?
5. 3/8 + 1/8 = ?
6. 5/6 − 1/3 = ?
7. 1/2 + 1/3 = ?
8. 7/10 − 2/5 = ?
9. 1/6 + 1/2 = ?
10. 3/4 − 1/2 = ?
Answer key — Adding & Subtracting Fractions
- B — 1/2. Same denominator, add the numerators: 1 + 1 = 2, so 2/4 = 1/2.
- C — 2/5. Same denominator, subtract the numerators: 3 − 1 = 2, so 2/5.
- B — 1/2. Common denominator 6: 1/3 = 2/6, then 2/6 + 1/6 = 3/6 = 1/2.
- C — 5/12. Common denominator 12: 2/3 = 8/12, 1/4 = 3/12, then 8/12 − 3/12 = 5/12.
- C — 1/2. Same denominator: 3 + 1 = 4, so 4/8 = 1/2.
- B — 1/2. Common denominator 6: 1/3 = 2/6, then 5/6 − 2/6 = 3/6 = 1/2.
- C — 5/6. Common denominator 6: 1/2 = 3/6, 1/3 = 2/6, then 3/6 + 2/6 = 5/6.
- B — 3/10. Common denominator 10: 2/5 = 4/10, then 7/10 − 4/10 = 3/10.
- B — 2/3. Common denominator 6: 1/2 = 3/6, then 1/6 + 3/6 = 4/6 = 2/3.
- C — 1/4. Common denominator 4: 1/2 = 2/4, then 3/4 − 2/4 = 1/4.
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