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 rectangular plot measuring 90 metres by 50 metres is to be enclosed by wire fencing. If the poles of the fence are kept 10 metres apart, how many poles will be needed ?

 Option A: 28

 Option B: 56

 Option C: 57

 Option D: 58

 Option E: None of these

Answer: Option A


Question: Question: A man's speed with the current is 20 kmph and speed of the current is 3 kmph. The Man's speed against the current will be

 Option A: 11 kmph

 Option B: 12 kmph

 Option C: 14 kmph

 Option D: 17 kmph

 Option E: None of these

Answer: Option C


Question: Question: If a+b=−6, and a=10/b, what is the value of a^2+b^2?

 Option A: 22

 Option B: 24

 Option C: 16

 Option D: 18

 Option E: 20

Answer:
Option C