If m, n are positive integers, what is the value of mn?

[Max@Math Revolution]

If m, n are positive integers, what is the value of mn?
1) m/n=7/15
2) The greatest common divisor of m and n is 3

[Max@Math Revolution]

There are 2 variables in the original condition. Hence, there is high chance that C is the correct answer. Using both the condition 1) and the condition 2), we get m=(7)(3) and n=(15)(3). Thus, the correct answer is C.

- Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.