A and B finish the job in 15 days.while A,B and C can finish it in 10 days . C alone will finish the job in	Choose the correct choice from the following options:
A) 40 days	B) 30 days	C) 60 days	D) 70 days	E) 50 days

Rationale: "explanation : 10 = ( 15 * x ) / ( 15 + x ) 150 + 10 x = 15 x 5 x = 150 x = 30 answer : option b"
Answer: B