The ratio of investments of two partners P and Q is 7:5 and the ratio of their profits is 7:13. If P invested the money for 5 months, find for how much time did Q invest the money? Choose the most appropriate option:
A) 19 B) 17 C) 13 D) 10 E) 12
7*5: 5*x = 7:13   x = 13   Answer: 13
<result>C</result>
The ratio of investments of two partners P and Q is 7:5 and the ratio of their profits is 7:13. If P invested the money for 5 months, find for how much time did Q invest the money?