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: If |x^2 20| = x, which of the following could be the value of x?

Option A: -5

Option B: -4

Option C: 1

Option D: 4

Option E: 10

Answer: Option D

Question: Question: A coin is tossed live times. What is the probability that there is at the least one tail?

Option A: 31/32

Option B: 31/35

Option C: 31/31

Option D: 31/36

Option E: 31/37

Answer:
Option A