Where possible simplify the fractions
1. 2/3 − 2/5 =
2. 2/5 − 1/6 =
3. 2/3 − 4/7 =
4. 3/4 − 3/8 =
5. 4/9 − 4/7 =
6. 4/5 − 2/3 =
7. 2/3 − 1/5 =
8. 1 1/7 − 4 1/2 =
9. 1 3/4 − 1 4/7 =
10. 2 1/9 − 3 1/8 =