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: The ratio of a to b to c is 2 to 3 to 4, and a, b, c are positive integers. If the average (arithmetic mean) of the three numbers is 36, what is the value of a?

 Option A: 21

 Option B: 24

 Option C: 25

 Option D: 27

 Option E: 30

Answer: Option B


Question: Question: If a Bus is travelling at a speed of 45 kmph, crosses a pole in 1 sec, then the length of train is?

 Option A: 12 m

 Option B: 12.3 m

 Option C: 12.5 m

 Option D: 12.8 m

 Option E: 13 m

Answer: Option C


Question: Question: Walking across campus, a student interviewed a group of students. 25% of the students took a finance class last semester, 51% took a marketing class last semester, and 40% took neither a finance nor a marketing class last semester. What percent of the students in the group took both a finance and a marketing class?

 Option A: 60%

 Option B: 50%

 Option C: 25%

 Option D: 16%

 Option E: 10%

Answer:
Option D