Quote:
If the power of an engine grows by 10% when the number of its cylinders is increased by one, which of the following is closest to the ratio of the power of a 9-cylinder engine to that of a 12-cylinder engine?
(A) 0.69
(B) 0.71
(C) 0.72
(D) 0.75
(E) 0.78
(A) 0.69
(B) 0.71
(C) 0.72
(D) 0.75
(E) 0.78
this worked best for me
Assume that 9 cylinders has a power output of 100%, then...
9 cylinders: 100
10 cylinders: 100 + 10 = 110
11 cylinders: 110 + 11 = 121
12 cylinders: 121 + 12 = 133
Thus, the ratio of 9 cylinders : 12 cylinders is...
100/133 = 0.75