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: In 165 litres of mixtures of milk and water, water is only 28%. The milkman sold 40 litres of this mixture and then he added 30 litres of pure milk and 13 litres of pure water in the remaining mixture. What is the percentage of water in the final mixture?

 Option A: 29.35%

 Option B: 28. 57%

 Option C: 24. 57%

 Option D: 27. 75%

 Option E: 26. 57%

A: Option B
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Q: Question: The price of 10 chairs is equal to that of 4 tables. The price of 15 chairs and 2 tables together is Rs. 4000. The total price of 12 chairs and 3 tables is:

 Option A: Rs. 3500

 Option B: Rs. 3750

 Option C: Rs. 3840

 Option D: Rs. 3900

 Option E: None

A:
Option D
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