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1. 3 / 8 + 2 / 8 = 5/8
2. 4 / 13 + 2 / 13 = 6/13
3. 6 /7 + 2 / 7 = 8/7
4. 9 / 10 - 6 / 10 = 3/10
5. 13 / 15 - 4 / 15 = 17/15
6. 6 / 8 + 3 / 4 = 6/8 +6/8 =12/8 = 3/2
7. 7 / 8 + 1 / 2 = 7/8 +4/8 = 11/8
8. 4 / 12 + 2 / 8 = 8/24 + 6/24 = 14/24 = 7/12
9. 6 / 10 + 3 /5 = 6/10+6/10 = 12/10 = 6/5
10. 7 / 9 + 2 / 8 = 56/72 + 18/72 = 74/72 = 37/36