In director John McTiernan’s Die Hard with a Vengeance (1995), lead characters John McClane (Bruce Willis) and Zeus Carver (Samuel L. Jackson) are forced to take part in a deadly game of cat and mouse, orchestrated by the mysterious villain called ‘Simple Simon’. Simon has placed bombs throughout the city of New York, and McClane and Carver must race across the city to defuse the devices before they explode.
During the course of the story, Simon leads McClane and Carver to a water fountain, which contains one of the bombs. Here the two characters are also presented with a puzzle involving two water containers.
One of the containers has the capacity to store five gallons of liquid. The other container has the capacity for three gallons of liquid.
McClane and Carver are told to fill one of the bottles with exactly four gallons of water. If they can do this, without the aid of any measuring equipment, this will disarm the bomb.
After a short discussion about how to approach the puzzle, the story briefly cuts away to a new scene. When the story cuts back to McClane and Carver the pair suddenly work out the solution and manage to defuse the bomb.
But the solution is not made clear to the audience. The characters somehow have the water they need to solve the puzzle.
So, how do you solve the ‘4-gallon’ puzzle?
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Solving the ‘4-gallon’ puzzle
The solution to the puzzle is quite simple, but requires a few steps to complete. So, if you have ever wondered how McClane and Carver solve the water puzzle in Die Hard with a Vengeance, here is what they do.
- Step 1 – Fill up the 5-gallon container in full.
- Step 2 – Pour liquid from the 5-gallon container into the 3-gallon container, until the 3-gallon container is full. This leaves two gallons of liquid remaining in the 5-gallon container.
- Step 3 – Empty the 3-gallon container.
- Step 4 – Pour the leftover two gallons of liquid from the 5-gallon container into the 3-gallon container. This will leave one gallon of space remaining in the 3-gallon container.
- Step 5 – Fill up the 5-gallon container one final time.
- Step 6 – Using the 5-gallon container, pour liquid into the 3-gallon container to fill up the one gallon of space.
This has now removed one gallon from the 5-gallon container. The 5-gallon container now holds four gallons of liquid and the puzzle is solved!
A simple solution that seems far more complicated than it is.
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If you’re a fan of the Die Hard movie series (and who isn’t?), then you may wish to know that the book that inspired the original movie is currently available in paperback.
The novel, Nothing Lasts Forever, by Roderick Thorp provided the basis for Die Hard and therefore helped kick-start one of the best-loved action movie franchises. The 245-page book is available in paperback, as well as on Kindle.
Nothing Lasts Forever is available from all good book stockists, including Amazon UK and Amazon US.
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Thank you for stopping by It’s A Stampede! to read this post about Die Hard with a Vengeance. I hope I have solved a problem which has perplexed you since 1995.
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One Response to Explaining the ‘four gallon’ puzzle in Die Hard with a Vengeance
Fill 3 -> Empty in 5 (3 is empty, 5 has 3 gallons)
Fill 3 -> Empty in 5 (3 has 1 gallon, 5 is full)
Empty 5 (3 has 1 gallon, 5 is empty)
Empty 3 in 5 (3 is empty, 5 has 1 gallon)
Fill 3 -> Empty in 5 (3 is empty, 5 has 4 gallons)
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