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: A cistern can be filled by a tap in 3 hours while it can be emptied by another tap in 9 hours. If both the taps are opened simultaneously, then after how much time will the cistern get filled?

 Option A: 2.9 hrs

 Option B: 4.5 hrs

 Option C: 2.9 hrs

 Option D: 7.2 hrs

 Option E: 8.6 hrs
Option B

Question: On dividing a number by 7, we get 5 as quotient and 0 as remainder. On dividing the same number by 11, what will be the remainder?

 Option A: 2

 Option B: 5

 Option C: 8

 Option D: 1

 Option E: 3
Option A

Question: The length of the bridge, which a train 100 metres long and travelling at 45 km/hr can cross in 30 seconds, is:

 Option A: 230

 Option B: 240

 Option C: 245

 Option D: 250

 Option E: 275

Option E