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: The average age of 15 students of a class is 15 years. Out of these, the average age of 4 students is 14 years and that of the other 10 students is 16 years, The age of the 15th student is

 Option A: 11

 Option B: 12

 Option C: 9

 Option D: 14

 Option E: 15

SOLUTION: Option C

PROBLEM: Question: The average of first seven prime numbers which are between 30 and 70 is

 Option A: 35.4

 Option B: 42

 Option C: 44.4

 Option D: 57

 Option E: 67

SOLUTION: Option C

PROBLEM: Question: Which of the following has a decimal equivalent that is a terminating decimal?

 Option A: 2/3^20

 Option B: 3^5/20^3

 Option C: 2^3/3^2

 Option D: 8^2/7^5

 Option E: 3^6/6^3

SOLUTION:
Option B