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 rent a pasture for 10 months. A put in 80 cows for 7 months. How many can B put in for the remaining 3 months, if he pays half as much again as A?

 Option A: 388

 Option B: 277

 Option C: 266

 Option D: 280

 Option E: 191

A: Option D
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Q: Question: A and B complete a work in 6 days. A alone can do it in 10 days. If both together can do the work in how many days?

 Option A: 3.75

 Option B: 3.76

 Option C: 3.79

 Option D: 3.74

 Option E: 3.71

A: Option A
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Q: Question: Two pipes A&B can fill a tank in 24 min and 32 min respectively. If both the pipes are opened simultaneously, after how much time B should be closed so that the tank is full in 18 min.

 Option A: 8 min

 Option B: 3 min

 Option C: 21 min

 Option D: 23 min

 Option E: 24 min

A:
Option A
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