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: 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

Answer: Option B


Question: Question: If a Bus is travelling at a speed of 45 kmph, crosses a pole in 1 sec, then the length of train is?

 Option A: 12 m

 Option B: 12.3 m

 Option C: 12.5 m

 Option D: 12.8 m

 Option E: 13 m

Answer: Option C


Question: Question: The length of a rectangular landscape is 4times its breadth. There is a playground in it whose area is 1200 square mtr & which is 1/3rd of the total landscape. What is the length of the landscape?

 Option A: 100

 Option B: 110

 Option C: 120

 Option D: 140

 Option E: 150

Answer:
Option C