If 3 men can complete a work in 12 days, how many days will it take for 5 men to complete the same work?

Answer: A. 8 days
If 3 men complete the work in 12 days, their combined work rate is 1/12. Therefore, 1 man would take 36 days to complete the work alone. 5 men would take 36/5 = 7.2 days, which rounds to 8 days.
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