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: P is three times as fast as Q and working together, they can complete a work in 18 days. In how many days can Q alone complete the work?

 Option A: 24

 Option B: 77

 Option C: 88

 Option D: 55

 Option E: 778

A: Option A
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Q: Question: A seller of used cars has 18 cars to sell and each of his clients selected 3 cars that he liked most. If each car was selected exactly thrice, how many clients visited the garage?

 Option A: 8

 Option B: 10

 Option C: 12

 Option D: 18

 Option E: 16

A: Option D
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Q: Question: A certain manufacturer of cake, muffin, and bread mixes has 100 buyers, of whom 50 purchases cake mix, 40 purchase muffin mix, and 15 purchase both cake mix and muffin mix. If a buyer is to be selected at random from the 100 buyers, what is the probability that the buyer selected will be one who purchases neither cake mix nor muffin mix?

 Option A: 1/10

 Option B: 3/10

 Option C: 1/4

 Option D: 7/10

 Option E: 9/10

A:
Option C
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