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.
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Question: Question: A die is rolled twice. What is the probability of getting a sum equal to 9?

 Option A: 2/3

 Option B: 2/9

 Option C: 1/3

 Option D: 1/9

 Option E: 1/10

Answer: Option D


Question: 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

Answer: Option D


Question: Question: At what rate percent of simple interest will a sum of money double itself in 66 years?

 Option A: 6.54 %

 Option B: 4.54 %

 Option C: 1.51 %

 Option D: 1.94 %

 Option E: 5.54 %

Answer:
Option C