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 circular swimming pool is surrounded by a concrete wall 4 feet wide.if the area of the wall is 11/25 of the area of the pool, then the radius of the pool in feet is?

 Option A: 22

 Option B: 20

 Option C: 9

 Option D: 8

 Option E: 1

Answer: Option B


Question: Question: How much time will it take for an amount of Rs. 900 to yield Rs. 81 as interest at 4.5% per annum of simple interest?

 Option A: 2 years

 Option B: 3 years

 Option C: 1 year

 Option D: 4 years

 Option E: 5 years

Answer: Option A


Question: Question: Boy sells a book for Rs. 450 he gets a loss of 10 %, To gain 10 %, what should be the SP?

 Option A: Rs.320

 Option B: Rs.450

 Option C: Rs.550

 Option D: Rs.640

 Option E: Rs.680

Answer:
Option C