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: 210 students were asked in a survey if they preferred windows or mac brand computers. 60 students claimed that they preferred mac to windows brand computers. one third as many of the students who preferred mac to windows, equally preferred both brands. 90 of the students had no preference. how many of the students in the survey preferred windows to mac brand computers ?
Options: a. 25, b. 40, c. 50, d. 60, e. 75

Answer: b

Question: Problem: a train traveled the first d miles of its journey it an average speed of 50 miles per hour, the next d miles of its journey at an average speed of y miles per hour, and the final d miles of its journey at an average speed of 160 miles per hour. if the train ' s average speed over the total distance was 96 miles per hour, what is the value of y ?
Options: a. 68, b. 84, c. 90, d. 120, e. 160

Answer: e

Question: Problem: the l. c. m. of two numbers is 60. the numbers are in the ratio 2: 3. then sum of the number is :
Options: a. 28, b. 32, c. 40, d. 53, e. 50

Answer:
e