6) 9 6/15 - 5 3/5 + 4 4/15 + 2 2/5

Convert mixed numbers to improper fractions: 9 6/15 = 141/15, 5 3/5 = 28/5, 4 4/15 = 64/15, 2 2/5 = 12/5. The expression becomes: 141/15 - 28/5 + 64/15 + 12/5.

Find a common denominator, which is 15. Convert fractions: 28/5 = 84/15, 12/5 = 36/15. The expression is now: 141/15 - 84/15 + 64/15 + 36/15.

Perform the addition and subtraction: (141 - 84 + 64 + 36) / 15 = 157/15. Convert back to a mixed number: 10 7/15.