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 pharmaceutical company received $3 million in royalties on the first $20 million in sales of and then $8 million in royalties on the next $108 million in sales. By approximately what percentage did the ratio of royalties to sales decrease from the first $20 million in sales to the next $108 million in sales?

 Option A: 8%

 Option B: 15%

 Option C: 46%

 Option D: 52%

 Option E: 56%

A: Option C
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Q: Question: The average weight of a group of persons increased from 48 kg to 51 kg, when two persons weighing 78 kg and 93 kg join the group. Find the initial number of members in the group?

 Option A: 76

 Option B: 28

 Option C: 23

 Option D: 98

 Option E: 32

A:
Option C
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