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.

[Q]: 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
[A]: Option C


[Q]: Question: How many words can be formed by taking 4 letters at a time out of the letters of the word MATHEMATICS.

 Option A: 2154

 Option B: 2454.

 Option C: 2254

 Option D: 2354

 Option E: 1245
[A]: Option B


[Q]: Question: The simple interest on a sum of money will be Rs.500 after 10 years. If the principal is trebled after 5 years what will be the total interest at the end of the tenth year?

 Option A: 2261

 Option B: 2888

 Option C: 1200

 Option D: 2699

 Option E: 900
[A]:
Option E