SOLUTION: if it takes pipe A 20 days to fill a fish pond and pipe B 15 days to fill the same pond how long will it take both pipes together to fill the same fish pond

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Question 196804: if it takes pipe A 20 days to fill a fish pond and pipe B 15 days to fill the same pond how long will it take both pipes together to fill the same fish pond
Found 2 solutions by solver91311, Anthea Lawn:
Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website!

If A can do a job in x time periods, then A can do of the job in 1 time period. Likewise, if B can do the same job in y time periods, then B can do of the job in 1 time period.

So, working together, they can do

of the job in 1 time period.

Therefore, they can do the whole job in:

time periods.

John

Answer by Anthea Lawn(22) (Show Source):
You can put this solution on YOUR website!
In one day, pipe A will have filled a twentieth of the pond.
In one day, pipe B will have filled a fifteenth of the pond.
So with both pipes running, in one day, + of the pond will be filled.
To add these together, express them as fractions of 60 (since both 20 and 15 go into 60)
After one day + = of the pond is filled.
So the pond is full after days
(approx 8 days, 13 hours, 42 minutes)