When John can do a work in 15 days and Marry in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is?
Select the correct option:	A) 2/15	B) 3/25	C) 8/15	D) 9/15	E) None
A's 1 day's work =	1	;   15   B's 1 day's work =	1	;   20   (A + B)'s 1 day's work =	(	1	+	1	)	=	7	.   15	20	60   (A + B)'s 4 day's work =	(	7	x 4	)	=	7	.   60	15   Therefore, Remaining work =	(	1 -	7	)	=	8/15   15   8/15
<result>C</result>
When John can do a work in 15 days and Marry in 20 days. If they work on it together for 4 days, then the fraction of the work that is left is?