TASK DEFINITION: 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.
PROBLEM: 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

SOLUTION: Option C

PROBLEM: Question: A train covers a distance of 12 km in 10 min. If it takes 10 sec to pass a telegraph post, then the length of the train is?

 Option A: 100

 Option B: 110

 Option C: 200

 Option D: 130

 Option E: 140

SOLUTION: Option C

PROBLEM: Question: A person's salary is getting reduced by 20%. What percentage should be added to get back his
original salary?

 Option A: 25%

 Option B: 50%

 Option C: 75%

 Option D: 85%

 Option E: 95%

SOLUTION:
Option A