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: The amount of an investment will double in approximately 70/ p years, where p is the percent interest, compounded annually. If Thelma invests $ 60,000 in a long-term CD that pays 5 percent interest, compounded annually, what will be the approximate total value of the investment when Thelma is ready to retire 42 years later?

 Option A: $ 280,000

 Option B: $ 320,000

 Option C: $ 360,000

 Option D: $ 480,000

 Option E: $ 540,000

A: Option D
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Q: Question: How many litres of pure salt are there in 12 litres of a 25% solution?

 Option A: 1.14 litres

 Option B: 1.41 litres

 Option C: 2.56 litres

 Option D: 3 litres

 Option E: 34litres

A:
Option D
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