X And Y Can Do a Piece of Work in 20 Days and 12 Days Respectively. X Started The Work Alone and Then After 4 Days, Y Joined Him Till The Completion of The Work.

X And Y Can Do a Piece of Work in 20 Days and 12 Days Respectively. X Started The Work Alone and Then After 4 Days, Y Joined Him Till The Completion of The Work. How Long Did The Work Last?

Here, X and Y do work on separate days. X started the work some of the day and later Y joined the work, now we found how many days to complete the work.

Explanation:

Given X does work in 20 days and later Y joined the work in 12 days. But X starts the work alone and later Y will join after 4 days.

Here are the solutions:

X done the work in 4 days = (1/20 *4) = 1/5

Remaining work day = (1/5 - 1) = 4/5

(X + Y) To combined effort of both X and Y individuals working together for 1 day = (1/12 + 1/20) = 8/60 = 2/15

So the remaining 4/5 work day, work well be done both X and Y in (15/2 * 4/5) = 6 days

X and Y to take time to complete the work =(6 + 4) = 10 Days