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 women purchased 3 towels @ Rs.100 each, 5 towels @ Rs.150 each and two towels at a certain rate which is now slipped off from his memory. But she remembers that the average price of the towels was Rs.145. Find the unknown rate of two towels?

 Option A: A

 Option B: B

 Option C: C

 Option D: D

 Option E: E

Answer: Option A


Question: Question: man buys an article for 10% less than its value and sells it for 10% more than its value. His gain or loss percent is?

 Option A: 12

 Option B: 76

 Option C: 26

 Option D: 20

 Option E: 12

Answer: Option D


Question: Question: Which of the following is equal to 3^k*7^(k-1)?

 Option A: 3*21^(k-1

 Option B: 7*21^(k-1

 Option C: 21^k

 Option D: 3*21^k 

 Option E: 21^(2k-1

Answer:
Option A