A man runs his car out of gas thereby completely emptying his 16 gallon tank. He only has a 3, a 6, and a 11 gallon container (and fortunately a wagon to carry the containers in) in his trunk. He has nothing else in which he can carry gas. He walks a few miles to a gas station, and as luck would have it the gauge on the pump is broken so he can not use that to measure the fuel. He is in a pretty remote area with only one gas station for miles. Gas costs $3.09⁹, and he only has a $50. Using only the containers provided, and only walking once to and from the gas station, how can he get exactly 16 gallons of gas into his car?

Fill 11g from pump.  --> 11g (11), 6g (0), 3g (0)

Fill 6g and 3g from 11g.  --> 11g (2), 6g (6), 3g (3)

Pour 3g into wagon.  --> w (3), 11g (2), 6g (6), 3g (0)

Pour 11g into 3g.  --> w (3), 11g (0), 6g (6), 3g (2)

Fill 3g from pump.  --> w (3), 11g (0), 6g (6), 3g (3)

Pour 6g and 3g into 11g.  --> w (3), 11g (9), 6g (0), 3g (0)

Fill 11g from wagon.  --> w (1), 11g (11), 6g (0), 3g (0)

Fill 6g and 3g from 11g.  --> w (1), 11g (2), 6g (6), 3g (3)

Pour 3g into wagon.  --> w (4), 11g (2), 6g (6), 3g (0)

Pour 11g into 3g.  --> w (4), 11g (0), 6g (6), 3g (2)

Fill 3g from pump.  --> w (4), 11g (0), 6g (6), 3g (3)

Pour wagon and 3g into 11g.  --> w (0), 11g (7), 6g (6), 3g (0)

Fill 3g from pump.  --> w (0), 11g (7), 6g (6), 3g (3)

Take the containers with a total of 16 gallons of gas back to the car using the wagon.

One trip, exactly 16 gallons.  The trick here is using the wagon to hold gas.

Edited on September 22, 2007, 4:18 pm

Edited on September 22, 2007, 4:27 pm

Posted by Guest on 2007-09-22 16:17:44