A man's car runs out of gasoline. His car tank holds exactly 13 gallons. He has three empty unmarked containers which can hold 3 gallons, 6 gallons, and 11 gallons. Using only these containers at the gas station, how can the man bring back exactly 13 gallons?

(He is not allowed to buy over 13 gallons and dispose of the extra.)

fill up the 6g. pure it in the 11g. do this again.
you can only pure i 5g, and the 6g container will be left with 1g. mark the level of 1g and then pure it into the 3g. now you can fill the 6g container up to the level of 1g. this gives you 13g.

Posted by bik88 on 2003-04-18 09:17:11