A and B can finish a work in 7 days and 8 days respectively.if both do work one day and leave one day.and A start the work then in how much days work will finish?
Choose the correct choice from the following answers
A) 52 / 7	B) 8	C) 14 / 2	D) 6	E) 43 / 6

Rationale: ( a + b ) work in 2 days = [ 1 / 7 + 1 / 8 ] = 15 / 56 ( a + b ) work in 6 days = 45 / 56 now , the turn of a , work of a in 1 day = 1 / 7 . till now completed work = [ 45 / 56 + 1 / 7 ] = 53 / 56 , remaining work = [ 1 - 53 / 56 ] = 3 / 56 now , turn of b , 1 / 8 work b do in 1 day so , 3 / 56 part of work b do = [ 8 * 3 / 56 ] = 3 / 7 days total time taken = 6 + 1 + 3 / 7 = 52 / 7 days answer a
Answer: A