You have a container with one gallon of red paint, and another container with one gallon of blue paint.
You take one cup of the red paint and pour it into the blue paint container. You stir the paint so that the two colors are mixed. You then take one cup of the mixed paint and add that to the red paint container.
Question: Do you have more red paint in the blue paint container, or more blue paint in the Red paint container?
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Comments: 18
I'll hold off, for now, revealing just what I believe that trick to be.
It's time to see your beautiful solution.
As there becomes red paint in the blue paint, where there was none initially, the blue paint container is the one with more red paint. That red paint had to come from somewhere, so the Red paint container must have LESS red paint.
Incidentally, as there is not sufficient paint transfer to convert either paint to another color, it could be argued that neither container contains more red paint.
The question was: Do you have more red paint in the blue paint container, or more blue paint in the Red paint container?
The answer: There is just as much red paint in the blue container as there is blue paint in the red container.
Both containers started out with one gallon of paint. They both ended up with one gallon of paint. Therefore whatever red paint ended up in the blue paint container must have been replaced in the red container by an equal amount of blue paint.
This is true regardless of whether you stir the red paint into the blue or not.
An interesting mental challenge.
Otherwise, its just simple math.
I don't find this statement true (given the way the question is phrased): Therefore whatever red paint ended up in the blue paint container must have been replaced in the red container by an equal amount of blue paint.
An equal amount of paint from the "blue" container, perhaps, but that container now contains a solution of 16/17 blue and 1/17 red (arguably no longer "blue" paint)--which is what is returned to the "red" container.
Anyway, if that's not right, I'm still missing something in the semantics here. And would welcome enlightenment!
A teaspoon of tea in a cup of coffee, for instance.
And the answer is in many riddle books.
Thanks for sharing it and making us put on our thinking caps.
I wish that I could say I was able to figure this one out by myself when I first heard it.