A: 3 1/5 is closest to 3, because 1/5 is less than 1/2. 5 7/9 is closest to 6, for the same reasons. 3 + 6 = 9
B: 15 5/7 is rounded to 16. 8 2/9 is rounded to 8. 16 - 8 = 8.
C: 1 5/8 is rounded to 2. 5 2/5 is rounded to 5. 2 + 5 = 7
D: 10 1/4 is rounded to 10. 1 11/15 is rounded to 2. 10 - 2 = 8
E: 2 7/10 is rounded to 3. 4 8/9 is rounded to 5. 3 + 5 = 8.
In conclusion, the one that is closest to 8 is B, D, E.
