Subject: mathqa
Question: the ratio of a to b is 4 to 5 , where a and b are positive . if x equals a increased by 75 percent of a , and m equals b decreased by 60 percent of b , what is the value of m / x ?
Option: 
A: 5 / 4
B: 2 / 7
C: 4 / 5
D: 2 / 5
Answer: B