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.

[EX Q]: Question: Two pipes A&B can fill a tank in 24 min and 32 min respectively. If both the pipes are opened simultaneously, after how much time B should be closed so that the tank is full in 18 min.

 Option A: 8 min

 Option B: 3 min

 Option C: 21 min

 Option D: 23 min

 Option E: 24 min
[EX A]: Option A

[EX Q]: Question: If x and y are integers, what is the least positive number of 24x+18y?

 Option A: 3

 Option B: 6

 Option C: 9

 Option D: 12

 Option E: 15
[EX A]: Option B

[EX Q]: Question: A person was asked to state his age in years. His reply was , "Take my age 5 years hence, multiply it by 3 and subtract 3 times my age 5 years ago and you will know how old I am." What was the age of the person ?

 Option A: 18

 Option B: 92

 Option C: 27

 Option D: 26

 Option E: 30
[EX A]:
Option E