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: The avg weight of A,B & C is 80 kg. If D joins the group, the avg weight of the group becomes 82 kg.If another man E who weights is 3 kg more than D Replaces A, Then the avgof B,C,D&E becomes 81 kg. What is the weight of A?

 Option A: 56

 Option B: 65

 Option C: 75

 Option D: 89

 Option E: 95

Answer: Option E


Question: Question: A and B together can do a work in 3 days. If A alone can do it in 12 days. In how many days can B alone do it?

 Option A: 4

 Option B: 6

 Option C: 8

 Option D: 10

 Option E: 25

Answer: Option A


Question: Question: If m and n are positive integers and n ≠ 1, then mn(n −1) is

 Option A: m-n

 Option B: m+n

 Option C: mn

 Option D: mn^2 -mn

 Option E: mn^2

Answer:
Option D