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 sequence contains y numbers of alternating positive and negative numbers, If the first number is postive and y is an even number, how many negative numbers are in it?

 Option A: (y+1

 Option B: (y-1

 Option C: y/(2+1

 Option D: y/(2-1

 Option E: y/2

Answer: Option E


Question: Question: A train 125 m long passes a man, running at 10 km/hr in the same direction in which the train is going, in 10 sec. The speed of the train is?

 Option A: 37 km/hr

 Option B: 50 km/hr

 Option C: 36 km/hr

 Option D: 26 km/hr

 Option E: 55 km/hr

Answer: Option E


Question: Question: A man can row with a speed of 15 kmph in still water. If the stream flows at 5 kmph, then the speed in downstream is?

 Option A: 27

 Option B: 27

 Option C: 20

 Option D: 99

 Option E: 2

Answer:
Option C