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.

Q: 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

A: Option B
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Q: Question: A number when divided by 5 gives a number which is 8 more than the remainder obtained on dividing the same number by 34. Such a least possible number N is

 Option A: 74

 Option B: N=75

 Option C: N=175

 Option D: N=680

 Option E: 690

A: Option B
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Q: Question: Tim came second in Math. When his mother asked him how much he had scored, he answered that he got the sum of the first 9 even numbers. His mother immediately worked out the answer. How much had he scored in Math?

 Option A: 80

 Option B: 90

 Option C: 30

 Option D: 70

 Option E: 60

A:
Option B
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