Work ...3

[nycmathguy]

Is my set up right?

A tank can be filled by pipe A in 3 hours and by pipe B in 5 hours. When the tank is full, it can be drained by pipe C in 4 hours. if the tank is initially empty and all three pipes are open, how many hours will it take to fill up the tank?

Pipe A = 1/3

Pipe B = 1/5

Pipe C = 1/4

Let 1/h = length of time it will all three pipes to fill the tank.

1/3 + 1/5 + + 1/4 = 1/h

You say?

 

[Country Boy]

Is my set up right?

A tank can be filled by pipe A in 3 hours and by pipe B in 5 hours. When the tank is full, it can be drained by pipe C in 4 hours. if the tank is initially empty and all three pipes are open, how many hours will it take to fill up the tank?

Pipe A = 1/3

Pipe B = 1/5

Pipe C = 1/4

My usual- A, B, and C are pipes, not rates of filling!

Let 1/h = length of time it will all three pipes to fill the tank.

No! "h" is the time it takes all three pipes to fill the tank. 1/h is the rate at which the tank is being filled.

1/3 + 1/5 + + 1/4 = 1/h

You say?

Because I hate unfinished problems, multiplying by 60h, 20h+ 12h+ 15h= 47h= 60.
h= 60/47= 1 13/47 hour, about one hour and 16 minutes.

 

[nycmathguy]

If you really hate unfinished problems, then skip my threads. Apparently you like hurting yourself. Sir, move on. In fact, I will place you on my ignore list starting right now.