Puzzle in Die Hard Movie!

memphis

Ok, I was watching Die Hard with a Vengeance the other day, and well, ya know the scene where they go to the water pond in the park and have to try use a 3 gallon and a five gallon jug to fit exactly 4 gallons and place it on the scales to disarm the bomb, how is it done?

I've rackled my brain and I'm still puzzled.

If ya fill the 5 to the top and pour it into the 3 gallon jug your left with 2 gallons in the 5 gallon jug, now where do I do to?

Downtime

The 3 gallon jug is the key.

Fill the 5 gallon jug.
Empty the 5 gallon jug into the 3 gallon jug, leaving 2 gallons.
Empty the 3 gallon jug.
Pour the 2 gallons from the 5 gallon jug into the 3 gallon jug.
Fill the 5 gallon jug and use it to fill the 3 gallon jug.
That leaves 4 gallons in the 5 gallon jug.

BattlingCheese

empty the 3 gallon and pour the 2 gallons of water left in the 5 gallon jug into the 3 gallon jug. Fill up the 5 gallon jug. Fill up the 3 gallon jug with one gallon of the water from the 5 gallon jug. Pour out the 3 gallon jug.

Now the 5 gallon jug has 4 gallons of water in it.

memphis

Of course, damn I'm thick!

Thanks guys!