A, B and C can do a piece of work in 6 days, 12 days and 30 days respectively. How long will they taken, if all the three work together?  Pick:	A) 3 9/17	B) 4	C) 5	D) 67	E) 9
1/6 + 1/12 + 1/30 = 17/60 =&gt; 60/17 =&gt; 3 9/17 days   3 9/17nswer:3 9/17
<result>A</result>
A, B and C can do a piece of work in 6 days, 12 days and 30 days respectively. How long will they taken, if all the three work together?