You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: A and B invests Rs.3000 and Rs.4000 respectively in a business. If A doubles his capital after 6 months. In what ratio should A and B divide that year's profit?

 Option A: 9:6

 Option B: 9:8

 Option C: 9:1

 Option D: 9:9

 Option E: 9:5

A: Option B
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Q: Question: A boat can travel with a speed of 25km/hr in still water. If the speed of the stream is 5km/hr, find the time taken by the boat to go 120km downstream.

 Option A: 1 hr

 Option B: 2 hrs

 Option C: 3 hrs

 Option D: 4 hrs

 Option E: 5 hrs

A: Option D
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Q: Question: P can do a work in 60 days. Q can do the same work in 9 days and R can do the same in 12 days. Q and R start the work and leave after 3 days. P finishes the remaining work in --- days.

 Option A: 7

 Option B: 8

 Option C: 9

 Option D: 15

 Option E: 25

A:
Option E
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