Inverse Proportion

[Bhandaripreeti]

If c is directly proportional to d and inversely proportional to e, and when and , which of the following is true for all values of c?

1) c=d/e

2) c=de/3

3) c=3d/4e

4) c= 4e/3d

5) c=12e/d

Ans 3

[kajcha]

c is directly proportional to d means c = a*d where "a" is a constant

c is inversely proportional to e. means c = b/e where "b" is a constant

together c can be written as

c = a*d*b/e. Only answer choice 3 is in this format.

[gmatguy16]

is the question complete,why is the answer not a ?