A and B can complete a job in 30 and 20 days respectively. They start working together and B leaves 5 days before the work is finished. In how many days is the total work finished?
Choose the correct choice from the following:	A) 20 days	B) 30 days	C) 12 days	D) 14 days	E) 15 days
explanation:   A and B can do the job in 30 and 20 days individually, so together they will take 30*20/(30 + 20) = 600/50= 
<gadget id="calculator">600/50</gadget>
<output>12</output>
12 days.   The work that A can do in 5 days is 1/6th. So, A left when 5/6th of the work was done or A left after  (5/6)*12= 
<gadget id="calculator"> (5/6)*12</gadget>
<output>10</output>
10 days   Total time taken= 10 + 5= 
<gadget id="calculator">10 + 5</gadget>
<output>15</output>
15 days.   Answer 15 days
<result>E</result>
A and B can complete a job in 30 and 20 days respectively. They start working together and B leaves 5 days before the work is finished. In how many days is the total work finished?