A,B,C can complete a piece of work in 3,9and 15 days respectively. Working together, they will complete the same work in how many days? Choose one
A) 45 / 23
B) 55 / 23
C) 61 / 57
D) 12 / 13
E) 22 / 23

Rationale: ( a + b + c ) ' s 1 day work = ( 1 / 3 ) + ( 1 / 9 ) + ( 1 / 115 ) = 23 / 45 a , b , c together will complete the work in 45 / 23 days answer is a
Answer: A