Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.
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Question: Problem: ages of two persons differ by 20 years. if 6 year ago, the elder one be 3 times as old the younger one, find their present age
Options: a. 12,28, b. 14,30, c. 16,36, d. 18,34, e. 19,34

Answer: c


Question: Problem: in 5 football games thus far this season, barry has run for 98, 107, 85, 89, and 91 yards. at a minimum, how many yards m will he need to gain this sunday if he wants to keep his season average above 100 yards ?
Options: a. 101, b. 116, c. m = 130, d. m = 131, e. m = 141

Answer: d


Question: Problem: the area of one square is x ^ 2 + 6 x + 9 and the area of another square is 4 x ^ 2 − 28 x + 49. if the sum of the perimeters of both squares is 56, what is the value of x ?
Options: a. 3, b. 4, c. 5, d. 6, e. 7

Answer:
d