instruction:
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.
question:
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
answer:
Option A


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: Some persons can do a piece of work in 12 days. Two times the number of these people will do half of that work in?

 Option A: 2 days

 Option B: 3 days

 Option C: 1 days

 Option D: 5 days

 Option E: 7 days
answer:

Option B