The answer to this is a=3
E + w = 50.....w = 50 - e
25e + 20w = 1090
25e + 20(50 - e) = 1090
25e + 1000 - 20e = 1090
25e - 20e = 1090 - 1000
5e = 90
e = 90/5
e = 18 <=== the east got 18
w = 50 - e
w = 50 - 18
w = 32 <=== the west got 32
7% Of 9000 is 630. Then subtract 630 from 9000. So your answer becomes 8370.
Answer: for 5/6 (-8/15) = - 4/9
