A group of men decided to do a work in 10days, but 5 of them became absent. If the rest of the group did the work in 12days, Find the original number of men?  Choose the correct choice from the following options.
A) 15  B) 20  C) 30  D) 25  E) 18

Rationale: original number of men = 5 * 12 / ( 12 - 10 ) = 30 answer is c
Answer: C