SOLUTION: one pipe can fill a tank in 12 hours, and another can fill the tank in 8 hours. how long will it take both pipes working together to fill the tank?

Question 547846: one pipe can fill a tank in 12 hours, and another can fill the tank in 8 hours. how long will it take both pipes working together to fill the tank?
Found 2 solutions by solver91311, josmiceli:
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

My calculator said it, I believe it, that settles it

Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Add their rates of filling
1st pipe's rate = ( 1 tank ) / ( 12 hrs )
2nd pipe's rate = ( 1tank ) / ( 8 hrs )
Let = hrs to fill tank using both pipes

Multiply both sides by

It will take 4 hrs and 48 min with both pipes
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