arithmetic - gaurav and shravan can together finish a work in 30 days they worked together for 20 days and then shravan left after another 20 days gaurav finished the remaining work in how many days gaurav alone can finish the job - skillgun

Let A = Gaurav, B = Shravan.
(A + B)'s 20 days' work = (1/30 x 20 ) = 2/3
Remaining work = 1 - 2/3= 1/3
Now, 1/3 work is done by A in 20 days.
.'. Whole work will be done by Gaurav in (20 x 3) = 60 days.