A puzzle for the smart ones?

Ok, start by pouring 3 pints into the 5 pint beaker. Fill up the 3 pint beaker again and pour it into the 5 pint beaker that already has 3 pints in it. That leaves you with 1 pint in the 3 pint beaker. Empty the 5 pint beaker and pour in the 1 pint you have left in the 3 pint beaker. Now fill the 3 pint beaker again and add it to the 1 pint in the 5 pint beaker and bingo, you got 4 pints!