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: the lcm of two numbers is 2310 and hcf is 55. if one of the numbers is 210. then what is the other number ?
Options: a. 715, b. 825, c. 330, d. 605, e. 465

A: d
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Q: Problem: a clock shows the time as 9 a. m. if the minute hand gains 7 minutes every hour, how many minutes will the clock gain by 6 p. m. ?
Options: a. 30 min, b. 35 min, c. 63 min, d. 50 min, e. 55 min

A: c
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Q: Problem: virginia, adrienne, and dennis have taught history for a combined total of 96 years. if virginia has taught for 9 more years than adrienne and for 12 fewer years than dennis, for how many years has dennis taught ?
Options: a. 23, b. 32, c. 35, d. 41, e. 42

A:
e
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