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 reduction of 20% in the price of salt enables a lady to obtain 10kgs more for Rs.100, find the original price per kg?

 Option A: Rs.3.2

 Option B: Rs.2.9

 Option C: Rs.2.5

 Option D: Rs.5.2

 Option E: Rs.2.1

A: Option C
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Q: Question: The number which exceeds 16% of it by 42 is?

 Option A: 50

 Option B: 25

 Option C: 52

 Option D: 58

 Option E: 60

A: Option A
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Q: Question: A train passes a station platform in 36 sec and a man standing on the platform in 20 sec. If the speed of the train is 54 km/hr. What is the length of the platform?

 Option A: 120 m

 Option B: 240 m

 Option C: 300 m

 Option D: 500 m

 Option E: 550 m

A:
Option B
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