Difficulty: Tricky
A recipe for making ice cream requires 1 litre of milk. Unfortunately, you only have an empty 5-litre bucket and an empty 3-litre bottle. How will you measure just 1 litre of milk for your recipe?
Need a hint?
You can pour milk into one container and then transfer it to the other container.
Brainteaser answer
Fill the 3-litre bottle with milk and then transfer it to the 5-litre bucket. This leaves room for another 2 litres of milk in the bucket.
Fill the 3-litre bottle with milk again and then transfer as much of it as fits in the 5-litre bucket without spilling. Only another 2 litres will fit, leaving 1 litre of milk in the bottle for your recipe.
Did you find another solution? Leave it in the comments!
2 responses
That’s the simplest solution I thought of, and was disappointed there wasn’t a more ingenious answer.
I also have an alternate solution, that’s a bit wasteful:
Fill the 5-litre bucket with milk and then transfer as much of it as fits in the 3-litre bottle without spilling. Empty out the 3-litre bottle, then transfer the remaining 2 litres of milk from the 5-litre bucket to the 3-litre bottle.
Again fill the 5-litre bucket with milk and then transfer as much of it as fits in the 3-litre bottle without spilling. Only another 1 litre will fit, leaving 4 litres of milk in the bucket.
Empty out the 3-litre bottle again, then transfer as much milk from the 5-litre bucket as fits in the 3-litre bottle without spilling. Only 3 litres will fit, leaving 1 litre of milk in the bucket for your recipe.
The bigger brainteaser though is who wrote the brainteaser: Mike McRae, as stated here on the website, or Ariel Marcy, as stated in the email?
Hi Peter, thanks so much for your creative, if milk-wasting solution! Hope you treat yourself to a scoop or two of ice cream to celebrate. To answer your ‘bigger brainteaser’, Mike McRae wrote the brainteaser and I merely uploaded it.
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