. X can complete a work in 20 days, Y in 30 days, and Z in 40 days. All of them started working together. But after 5 days, X left. After 3 more days Y also left the work. In how many days can Z complete the remaining work ?
Answers
I have two answers, the correct answer depends on the meaning of the question.
1st Answer:
If you mean Z needs to complete only his remaining work.
After 5 days X left
After 3 more days Y left
This means (5+3) 8 days have passed
Z takes 40 days to complete the work
Take away 8 days from 40 days (40 - 8) and we get 32
Therefore, Z will complete his remaining work in 32 more days
2nd Answer:
If you mean that because the two of them left, Z will need to do their work too.
When compared to X, Z takes twice the time to complete the work
If X left the 15 (20 - 5) days work remaining, then Z will take 30 days to complete it (15x2)
When compared to Y, 1.5 the time to complete the work
If Y left, leaving the 22 (30 - 8) days work remaining, then Z will take 33 days to complete it
But let's not forget, Z has his work to do too, he will need 32 more days to complete his work
Therefore, Z will take (30+33+32) 95 days to complete all the remaining work
Hope it helps