>Julio can fill a water tank in 4 min using a large hose. He takes 6 min using a smaller hose. How long will he take if he uses both hoses?
The key is to note what happens in one minute.
In 1 minute using the large hose 1/4 of the tank is filled.
In 1 minute using the small hose 1/6 of the tank is filled.
Now, can you figure out how much of the tank is filled in 1 minute when both hoses are used? From that you should be able to calculate how long it takes to fill the tank.
For instance, say that in one minute 3/8 of a pool is filled.
Then 1/8 of the pool is filled in 1/3 of a minute.
And 8/8 of the pool is filled in 8/3 of a minute. (8/8 of the pool is all of it.)
Maybe you get the idea???
