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: 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

A: Option A
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Q: Question: When n is divided by 19, the remainder is 7. When n is divided by 11, the quotient is equal to Z, and the remainder is equal to 7. Z must be divisible by which of the following numbers?

 Option A: 16

 Option B: 18

 Option C: 20

 Option D: 19

 Option E: 22

A: Option D
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Q: Question: On adding four times the age of Chris Hemsworth four years from now to five times his age five years from now, we will get ten times his current age.
How old is Chris right now?

 Option A: 38 years

 Option B: 24 years

 Option C: 40 years

 Option D: 41 years

 Option E: 29 years

A:
Option D
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