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.

Example Input: Question: Working alone at its constant rate, machine K took 3 hours to produce 1/5 of the units produced last Friday. Then machine M started working and the two machines, working simultaneously at their respective constant rates, took 6 hours to produce the rest of the units produced last Friday. How many hours would it have taken machine M, working alone at its constant rate, to produce all of the units produced last Friday?

 Option A: 10

 Option B: 12

 Option C: 15

 Option D: 25

 Option E: 30
Example Output: Option C

Example Input: Question: The functions f and g are defined for all the positive integers n by the following rule: f(n) is the number of perfect squares less than n and g(n) is the number of primes numbers less than n. If f(x) + g(x) = 16, then x is in the range:

 Option A: 30 < x < 36

 Option B: 30 < x < 37

 Option C: 31 < x < 37

 Option D: 31 < x < 38

 Option E: 32 < x < 38
Example Output: Option C

Example Input: Question: 33 1/3% OF 390?

 Option A: 80

 Option B: 90

 Option C: 110

 Option D: 120

 Option E: 130
Example Output:
Option E