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: Bat is bought for Rs.400 and sold at a gain of 20% find its selling price?

 Option A: Rs.320

 Option B: Rs.350

 Option C: Rs.370

 Option D: Rs.480

 Option E: None of these

A: Option D
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Q: Question: From a Group of 10 People, Including George and Nina, 3 people are to be selected at random to work on a certain project. What is the probability that 3 people selected will include George but not Nina

 Option A: 5/56

 Option B: 9/56

 Option C: 28/120

 Option D: 21/56

 Option E: 25/56

A: Option C
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Q: Question: Mary decided to save a certain amount of her monthly salary each month and her salary was unchanged from month to month. If Mary's savings by the end of the year from these monthly savings were SIX times the amount she spent per month, what should be the fraction of her salary that she spent each month?

 Option A: 1/2

 Option B: 3/4

 Option C: 1/3

 Option D: 2/3

 Option E: 1

A:
Option D
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