A can do a work in 15 days and B in 20 days. If they work on it together for 7 days, then the fraction of the work that is left is	Answers
A) 8/17 B) 7/15 C) 3/15 D) 8/15 E) 11/60
Person ( A ) ( B ) ( A+B )   Time - ( 15 ) ( 20 ) (-)   Rate - ( 20 ) ( 15 ) ( 35 )   Work -(300) (300) (300)   therefore A+B requires (300/35) days to complete entire work   For 1st 4 days they work  35 * 7= 
<gadget id="calculator"> 35 * 7</gadget>
<output>245</output>
245   Remaining work is 300 - 245= 
<gadget id="calculator">300 - 245</gadget>
<output>55</output>
55   Remaining fraction of work is= 55/300 = 11/60   Answer 11/60
<result>E</result>
A can do a work in 15 days and B in 20 days. If they work on it together for 7 days, then the fraction of the work that is left is