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 price of 2 sarees and 4 shirts is Rs. 1600. With the same money one can buy 1 saree and 6 shirts. If one wants to buy 12 shirts, how much shall he have to pay ?

 Option A: 4800

 Option B: none of these

 Option C: 3600

 Option D: 1200

 Option E: 2400

A: Option E
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Q: Question: A train running at the speed of 240 km/hr crosses a pole in 21 seconds. What is the length of the train?

 Option A: 1300 m

 Option B: 1350 m

 Option C: 1400 m

 Option D: 1450 m

 Option E: 1500 m

A:
Option C
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