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: Pipe A can fill a tank in 16 minutes and pipe B cam empty it in 24 minutes. If both the pipes are opened together after how many minutes should pipe B be closed, so that the tank is filled in 30 minutes?

 Option A: 20

 Option B: 16

 Option C: 24

 Option D: 28

 Option E: 21

Answer: Option E


Question: Question: A certain vehicle is undergoing performance adjustments during a set of three trials on an 8-mile track. The first time it travels around the track at a constant rate of p miles per minute, the second time at a constant rate of p^2 miles per minute, and the third time at a constant rate of p^3 miles per minute. If the vehicle takes the same time to travel the first 18 miles of these trials as it does to travel the last 8 miles, how many minutes does it take to complete all three trials (not counting any time between trials)?

 Option A: 18

 Option B: 36

 Option C: 60

 Option D: 96

 Option E: 112 minutes

Answer: Option E


Question: Question: A squirrel has 13 nuts, then he finds 8 more nuts. Now how many nuts he have?

 Option A: 5

 Option B: 9

 Option C: 21

 Option D: 11

 Option E: 16

Answer:
Option C