A work which could be finished in 9 days was finished 3 days earlier after 10 more men joined. The number of men employed was?  Choose the most appropriate option:
A) 18
B) 20
C) 22
D) 24
E) 26

Rationale: "explanation : x - - - - - - - 9 ( x + 10 ) - - - - 6 x * 9 = ( x + 10 ) 6 x = 20 answer : b"
Answer: B