10 - 3 и 3/4 ( 2 и 1/3 +1 и 2/5) : 1 5/9=?

Question

10 - 3 и 3/4 ( 2 и 1/3 +1 и 2/5) : 1 5/9=?

Answer 1

10 - 3 и 3/4 ( 2 и 1/3 +1 и 2/5) : 1 5/9 = 10 - 15/4 ( 7/3 + 7/5) : 14/9 

=10- 15/4*7/3 - 15/4*7/5 : 14/9 = (10 -35/4 - 21/4) : 14/9 =  - 16/4 : 14/9 = -4 : 14/9 =      - 18/7