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 train 125m long takes 6 sec to cross a man walking at 5kmph in a direction opposite to that of the train. Find the speed of the train?

 Option A: 65kmph

 Option B: 70kmph

 Option C: 75kmph

 Option D: 80kmph

 Option E: 85kmph

Answer: Option B


Question: Question: How many pieces of 0.85 metres can be cut from a rod 42.5 metres long?

 Option A: 30

 Option B: 40

 Option C: 50

 Option D: 60

 Option E: 70

Answer: Option C


Question: Question: A person can swim in still water at 12 km/h. If the speed of water 6 km/h, how many hours will the man take to swim back against the current for 6km?

 Option A: 3

 Option B: 4

 Option C: 5

 Option D: 6

 Option E: 7

Answer:
Option D