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: Read the following three equations:
5 ~ 4 ~ 3 ~ 9 = 4215
6 ~ 9 ~ 2 ~ 6 = 3816
4 ~ 7 ~ 3 ~ 3 = 1122
Now based on the rule that has been used, solve the following equation:
4 ~ 2 ~ 7 ~ 4 = ____

 Option A: 1416

 Option B: 2910

 Option C: 2940

 Option D: 3749

 Option E: 4470

Answer: Option A


Question: Question: 2 + 2^2 + 2^3 + ... + 2^8 = ?

 Option A: 510

 Option B: 310

 Option C: 210

 Option D: 410

 Option E: None of them

Answer:
Option A