The ratio of investments of two partners P and Q is 7:5 and the ratio of their profits is 7:9. If P invested the money for 5 months, find for how much time did Q invest the money?
Choose the correct answer:  A) 9  B) 17  C) 13  D) 10  E) 12
7*5: 5*x = 7:9   x = 9   9nswer: 9
<result>A</result>
The ratio of investments of two partners P and Q is 7:5 and the ratio of their profits is 7:9. If P invested the money for 5 months, find for how much time did Q invest the money?