Solution for #45

Alternate Solution #1

Fill the three-gallon tank from the eight-gallon. Dump the three-gallon tank into the five-gallon. Fill the three-gallon tank from the eight-gallon again and use that to fill the five-gallon. Now you've got two gallons in the eight-gallon tank, five gallons in the five-gallon tank, and one gallon in the three-gallon tank.

Dump the five-gallon tank into the eight-gallon tank. Put the gallon from the three-gallon tank into the five-gallon tank. Now you've got seven gallons in the eight-gallon tank and one in the five-gallon tank.

Fill the three-gallon tank from the eight-gallon tank. Dump the three-gallon tank into the five-gallon tank. You should now have four gallons in the eight-gallon tank and four gallons in the five-gallon tank.

Alternate Solution #2

Fill the five-gallon tank from the eight-gallon. Fill the three-gallon tank from the five-gallon. Pour the three-gallon tank back into the eight-gallon tank. Now you should have six gallons in the eight-gallon tank and two gallons in the five-gallon tank.

Dump the two gallons in the five-gallon tank into the three-gallon tank. Pour what you can from the eight-gallon tank into the five-gallon tank. Now you should have one gallon in the eight-gallon tank, five gallons in the five-gallon tank, and two gallons in the three-gallon tank.

Top off the three-gallon tank from the five-gallon, and dump the three-gallon tank into the eight-gallon tank.