Question

A can do a piece of work in 40 days. He works at it for 5 days and then B finishes it in 10 days.

In what time can A and B together finish it ?

Answer 1

Answer:Given

a can do a piece of work = 40 days

so, A's 1 day work =1/4

so, A's 8 day's work =8/40=1/5

remaining work = 1- 1/5= 4/5

Now, B can do 4/5 piece of work in =16 days

So, B’s 1 day's work = (4/5) /16= 4/ 5x6=1/20

Therefore, (A+B)’s 1 day's work = 1/40+1/20 =

1+2/40=3/40

∴ Both (A+B) can do a piece of work in =

1/days (3/40) = 40/3 days

= 13 1/3 days