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 together can do a work in 3 days. If A alone can do it in 12 days. In how many days can B alone do it?

 Option A: 4

 Option B: 6

 Option C: 8

 Option D: 10

 Option E: 25

A: Option A
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Q: Question: The radius of a wheel is 22.4 cm. What is the distance covered by the wheel in making 1500 resolutions?

 Option A: 2112 m

 Option B: 2704 m

 Option C: 2278 m

 Option D: 2288 m

 Option E: 2378 m

A: Option A
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Q: Question: Ramu bought an old car for Rs. 42000. He spent Rs. 10000 on repairs and sold it for Rs. 64900. What is his profit percent?

 Option A: 17%

 Option B: 19%

 Option C: 24.8%

 Option D: 14%

 Option E: 16%

A:
Option C
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