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: an article with cost price of 180 is sold at 15% profit. what is the selling price?

 Option A: 198

 Option B: 200

 Option C: 204

 Option D: 207

 Option E: 210

A: Option D
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Q: Question: Which of the following CANNOT be weighed using a balance scale and these unit weights: 1, 4, 7, and 10

 Option A: 13

 Option B: 15

 Option C: 17

 Option D: 19

 Option E: 21

A: Option A
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Q: Question: Find the odd man out
25, 49, 81, 121, 144, 169

 Option A: 49

 Option B: 121

 Option C: 144

 Option D: 169

 Option E: 25

A:
Option C
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