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: four bells commence tolling together and toll at intervals of 2, 4, 6, 8 seconds respectively. in 18 minutes, how many times do they toll together ?
Options: a. 43, b. 44, c. 45, d. 46, e. 47

Answer: c


Question: Problem: a merchant sells an item at a 20 % discount, but still makes a gross profit of 20 percent of the cost. what percent of the cost would the gross profit on the item have been if it had been sold without the discount ?
Options: a. 20 %, b. 40 %, c. 50 %, d. 60 %, e. 75 %

Answer: c


Question: Problem: on a certain road, 10 % of the motorists exceed the posted speed limit and receive speeding tickets, but 20 % of the motorists who exceed the posted speed limit do not receive speeding tickets. what percent of the motorists on that road exceed the posted speed limit ?
Options: a. 10.5 %, b. 12.5 %, c. 15 %, d. 22 %, e. 30 %

Answer:
b