The ratio of investments of two partners P and Q is 7:5 and the ratio of their profits is 7:11. If P invested the money for 5 months, find for how much time did Q invest the money?  Select:
A) 19  B) 17  C) 13  D) 11  E) 12

Rationale: "7 * 5 : 5 * x = 7 : 11 x = 11 answer : d"
Answer: D