pls answer this frds...
Attachments:
Answers
Answered by
1
Answer: 30 days.
Step-by-step explanation:
A can do it in 80 days.
Therefore , A's 1 day work=1/80
and so A's 10 day work=(1/80)*10=1/8.
So, a has done 1/8 of the work .
Work left to do= 1-(1/8)=(8-1)/8=7/8.
ATP,
B does 7/8 work in 42 days.
So , B does 1 work in 42*8/7 days=48 days
so B's 1 day work=1/48.
total 1 day work of A + B = 1/80 + 1/48
= (3+5)/240
= 8/240
= 1/30
So A's+B's 1 day work =1/30
so they take 30 days to do the work together.
Similar questions