A work which could be finished in 12 days was finished 3 days earlier after 10 more men joined. The number of men employed was?
Choose the correct choice:  A) 22  B) 20  C) 88  D) 71  E) 10

Rationale: x - - - - - - - 12 ( x + 10 ) - - - - 6 x * 12 = ( x + 10 ) 6 x = 10 \ answer : e
Answer: E