Add and subtract fractions with negatives

Give the answer as a fraction in lowest terms, or a whole number.

1. Evaluate: 3/10 − (−5/8) (Write a fraction in lowest terms, or a whole number.)
2. Evaluate: 4/5 − 4/5 (Write a fraction in lowest terms, or a whole number.)
3. Evaluate: −1/3 + 2/5 (Write a fraction in lowest terms, or a whole number.)
4. Evaluate: 5/8 − 5/8 (Write a fraction in lowest terms, or a whole number.)
5. Evaluate: −2/3 − (−3/4) (Write a fraction in lowest terms, or a whole number.)
6. Evaluate: 3/5 + 1/2 (Write a fraction in lowest terms, or a whole number.)
7. Evaluate: 1/2 − 7/10 (Write a fraction in lowest terms, or a whole number.)
8. Evaluate: −1/2 − 7/8 (Write a fraction in lowest terms, or a whole number.)
9. Evaluate: 4/5 + 2/3 (Write a fraction in lowest terms, or a whole number.)
10. Evaluate: −3/4 − 9/10 (Write a fraction in lowest terms, or a whole number.)
11. Evaluate: −1/3 − 1/4 (Write a fraction in lowest terms, or a whole number.)
12. Evaluate: 2/7 + (−1/7) (Write a fraction in lowest terms, or a whole number.)
13. Evaluate: 1/4 − 3/8 (Write a fraction in lowest terms, or a whole number.)
14. Evaluate: 1/4 + 3/7 (Write a fraction in lowest terms, or a whole number.)
15. Evaluate: 1/3 − 1/3 (Write a fraction in lowest terms, or a whole number.)
16. Evaluate: −2/3 + (−1/2) (Write a fraction in lowest terms, or a whole number.)
17. Evaluate: −1/3 + 4/15 (Write a fraction in lowest terms, or a whole number.)
18. Evaluate: 3/4 − 3/4 (Write a fraction in lowest terms, or a whole number.)
19. Evaluate: −1/2 − (−2/9) (Write a fraction in lowest terms, or a whole number.)
20. Evaluate: 1/2 + 2/3 (Write a fraction in lowest terms, or a whole number.)