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: Two pipes A and B can fill a tank in 15 min and 20 min respectively. Both the pipes are opened together but after 4 min, pipe A is turned off. What is the total time required to fill the tank?

 Option A: 14 min 19 sec

 Option B: 14 min 42 sec

 Option C: 14 min 20 sec

 Option D: 14 min 40 sec

 Option E: 14 min 10 sec

A: Option D
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Q: Question: John, Karen, and Luke collected cans of vegetables for a food drive. The number of cans that John collected was 1/2 the number of cans that Karen collected and 1/3 the number of cans that Luke collected. The number of cans that Karen collected was what fraction of the total number of cans that John, Karen, and Luke collected?

 Option A:  1/5

 Option B:  1/3

 Option C:  2/5

 Option D:  1/2

 Option E:  2/3

A:
Option B
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