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.

Question: How much time does a train 150 metres long running at 90 km/hr take to pass a pole?

 Option A: 7.9s

 Option B: 6s

 Option C: 7.5s

 Option D: 7.6s

 Option E: 7.4s
Option B

Question: The number of arrangements that can be made with the letters of the word COPY so that the vowels occupy the even places?

 Option A: 6

 Option B: 144

 Option C: 777

 Option D: 992

 Option E: 221
Option A

Question: A pipe can filled a tank in 40 minutes and another pipe can empty it in 1hour. If the tank is already half full and both the taps are opened together, then the tank is filled in how many minutes?

 Option A: 25min

 Option B: 20min

 Option C: 15min

 Option D: 10min

 Option E: 30min

Option A