There are 75 money managers in town A, 20 of whom have beaten a major

Question

There are 75 money managers in town A, 20 of whom have beaten a major index in the last three years. Moreover, 15 of those who have beaten a major index in the last three years have a crystal ball. If 13 of the money managers in town A neither have beaten a major index in the last three years nor have a crystal ball, how many more money managers would have to get a crystal ball so that 4/5 of the money managers would have a crystal ball?

A. 3
B. 7
C. 10
D. 12
E. 15

A. 3 
B. 7
C. 10
D. 12
E. 15

korrag · Answer

Putting the given values in a 2 variable matrix, we get the present number of managers who have a crystal ball as 57.
Assume we need to add "x" more money managers who have a crystal ball to get the required ratio of 4/5.

Hence, (57+x)/(75+x) = 4/5
We can see that x+75 needs to be a multiple of 5. By testing the values, we see that only x=15 fits.

Kurtosis · Answer

Major Index(only) + Crystal Ball(only) + Both + Neither = 75
Major Index(only) + Both + Neither = 20 + 13 = 33
Crystal Ball(only) = 42

Total Crystal Ball = 42 + 15 = 57

(57 + x)/(75 + x) = 4/5
285 + 5x = 300 + 4x 
x = 15

Answer: E

OreoShake · Answer

How is OA A? Shoudnt it be E?? Please help.

bumpbot · Answer

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There are 75 money managers in town A, 20 of whom have beaten a major

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