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: Mr. Evans will states that each of his children will receive an equal share of his estate and that his grandchildren will split a portion of the estate that is equal to the share received by each of his children. If Mr. Evans has 4 children and 5 grandchildren, then approximately what percentage of Mr. Evans estate will each grandchild receive?

 Option A: 20%

 Option B: 17%

 Option C: 4.0%

 Option D: 3.3%

 Option E: 2.8%

A: Option C
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Q: Question: Two pipes A and B can fill a tank in 15 min and 20 min respectively. Both the pipes are opened together but after 4 min, pipe A is turned off. What is the total time required to fill the tank?

 Option A: 14 min 19 sec

 Option B: 14 min 42 sec

 Option C: 14 min 20 sec

 Option D: 14 min 40 sec

 Option E: 14 min 10 sec

A: Option D
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Q: Question: A family consists of two grandparents, two parents and 6 grandchildren. The average age of the grandparents is 60 years, that of the parents is 30 years and that of the grandchildren is 5 years. What is the average age of family?

 Option A: 5/7years

 Option B: B

 Option C: C

 Option D: D

 Option E: E

A:
Option B
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