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: There are 3 questions in a question paper. If the questions have 4,3 and 2 solutions respectively, find the total number of solutions

 Option A: 24

 Option B: 25

 Option C: 30

 Option D: 40

 Option E: 54

A: Option A
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Q: Question: A man can do a piece of work in 5 days, but with the help of his son he can do it in 3 days. In what time can the son do it alone ?

 Option A: 13/2

 Option B: 19/2

 Option C: 21/2

 Option D: 15/2

 Option E: None

A: Option C
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Q: Question: Two trains 121 meters and 153 meters in length respectively are running in opposite directions, one at the rate of 80 km and the other at the rate of 65 kmph. In what time will they be completely clear of each other from the moment they meet?

 Option A: 7.19

 Option B: 6.8

 Option C: 7.2

 Option D: 7.15

 Option E: 7.11

A:
Option B
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