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?

(In reply to Solution by Guest)

Nicely worked out mathematical solution. I however do not know of a wagon that is water tight.  The problem says specifically a wagon to carry the containers in and nothing else in which he can carry gas. (that would include the wagon in my book).  The metal wagons have the steering mechanism coming up through the bottom, and the plastic ones I have seen have a hole in the bottom so they do not collect rain water sitting in your yard.

Not the solution I was looking for, but some could argue a viable solution. (Although I do not believe so.) I do like your thinking though and that is the idea behind these trick problems. Thanks.

Posted by jduval on 2007-09-23 10:51:27