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: The original price of a shirt was $20. It was decreased to $15 . What is the percent decrease of the price of this shirt.

 Option A: 25%

 Option B: 35%

 Option C: 45%

 Option D: 55%

 Option E: 65%

Answer: Option A


Question: Question: Find the sum lend at C.I. at 5 p.c per annum will amount to Rs.441 in 2 years?

 Option A: Rs.900

 Option B: Rs.800

 Option C: Rs.500

 Option D: Rs. 400

 Option E: Rs.200

Answer: Option D


Question: Question: A AND B CAN DO A WORK IN 12 DAYS, B AND C IN 15 DAYS, C AND A IN 20 DAYS. IF A, B AND C WORK TOGETHER, THEY WILL COMPLETE THE WORK IN:

 Option A: 5 DAYS

 Option B: 7 5/6 DAYS

 Option C: 10 DAYS

 Option D: 15 2/3 DAYS

 Option E: NONE OF THESE

Answer:
Option C