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: In a class of 40 students, 10 did not opt for math. 15 did not opt for science and 2 did not opt for either. How many students of the class opted for both math and science?

 Option A: 13

 Option B: 15

 Option C: 7

 Option D: 17

 Option E: 18

Answer: Option C


Question: Question: When positive integer k is divided by 5, the remainder is 2. When k is divided by 6, the remainder is 5. If k is less than 24, what is the remainder when k is divided by 7?

 Option A: 2

 Option B: 5

 Option C: 6

 Option D: 3

 Option E: 8

Answer: Option D


Question: Question: The average (arithmetic mean) of y numbers is x. If 10 is added to the set of numbers, then the average will be x - 5. What is the value of y in terms of x ?

 Option A: x/6 - 6

 Option B: x/6 - 5

 Option C: x/7 - 5

 Option D: x/5 - 3

 Option E: x/5 - 6

Answer:
Option D