A, B and C can do a work in 90, 30 and 45 days respectively. If they work together, in how many days will they complete the work? Options.
A) 15 days
B) 65 days
C) 16 days
D) 17 days
E) 19 days
One days's work of A, B and C = 1/90 + 1/30 + 1/45   = (1 + 3 + 2)/90 = 1/15   A, B and C together can do the work in 15 days.   15 daysnswer:15 days
<result>A</result>
A, B and C can do a work in 90, 30 and 45 days respectively. If they work together, in how many days will they complete the work?