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 school 50% of the students are younger than 10, 1/20 are 10 years old and 1/10 are older than 10 but younger than 12, the remaining 70 students are 12 years or older. How many students are 10 years old?

 Option A: 5

 Option B: 6

 Option C: 7

 Option D: 8

 Option E: 10

SOLUTION: Option E

PROBLEM: Question: On dividing 21 by a number, the quotient is 10 and the remainder is 1. Find the divisor.

 Option A: 1

 Option B: 2

 Option C: 4

 Option D: 6

 Option E: 7

SOLUTION: Option B

PROBLEM: Question: The sum of the present ages of two persons A and B is 60. If the age of A is twice that of B, find the sum of their ages 7 years hence?

 Option A: 58

 Option B: 74

 Option C: 62

 Option D: 70

 Option E: 74

SOLUTION:
Option B