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.
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Question: 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

Answer: Option A


Question: Question: The length and breadth of a rectangular floor are 16.25 metre and 12.75 metre respectively. Find how many minimum number of square tiles would be required to cover it completely?

 Option A: 375

 Option B: 2570

 Option C: 2800

 Option D: 3315

 Option E: None of these

Answer: Option D


Question: Question: A watch passes through three hands and each gains 25%. If the 3rd sells it for Rs250, what did the 1st pay for it?

 Option A: 110

 Option B: 120

 Option C: 128

 Option D: 143

 Option E: 145

Answer:
Option C