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: a van takes 5 hours to cover a distance of 495 km. what speed in kph should the van maintain to cover the same distance in 3 / 2 of the previous time ?
Options: a. 60, b. 63, c. 66, d. 69, e. 72

Answer: c


Question: Problem: the sum of the ages of 5 children born at the intervals of 3 year each is 60 year. what is the age of the youngest child ?
Options: a. 4 year, b. 6 year, c. 10 year, d. none of these, e. 9 year

Answer: b


Question: Problem: in a dairy farm, 55 cows eat 55 bags of husk in 55 days. in how many days one cow will eat one bag of husk ?
Options: a. 34 days, b. 40 days, c. 46 days, d. 50 days, e. 55 days

Answer:
e