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.

Q: Problem: a and b go around a circular track of length 200 m on a cycle at speeds of 36 kmph and 72 kmph. after how much time will they meet for the first time at the starting point ?
Options: a. 120 sec, b. 198 sec, c. 178 sec, d. 20 sec, e. 276 sec

A: d
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Q: Problem: a train which has 430 m long, is running 45 kmph. in what time will it cross a person moving at 9 kmph in same direction ?
Options: a. 56 sec, b. 43 sec, c. 36 sec, d. 29 sec., e. 19 sec.

A: b
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Q: Problem: a group of boy scouts and girls scouts is going on a rafting trip. 60 % of the scouts arrived with signed permission slips. if 45 % of the scouts were boy scouts and 50 % of the boy scouts arrived with signed permission slips, then what percentage of the girl scouts arrived with signed permission slips ? round to the nearest percent.
Options: a. 64, b. 68, c. 72, d. 76, e. 80

A:
b
****