I think it's more interesting that this poorly-worded "riddle" managed to find its way onto wikipedia:
A section titled "The Language Paradox" was removed on October 2:
> Careful wording must be used to ensure that the "paradox" is correct.
With the explanation: "This is 100% original research, which as noted contains errors"
So the only thing that makes the "paradox" interesting is that it's badly worded, but any commentary to that effect is original research, so in the end we're just left with a fairly unremarkable riddle on Wikipedia and grumpy people like myself complaining about it.
A very prevalent misunderstanding/error though - 'comparing fractions of different things' in general.
i.e. here the basic issue is that it's really more like two different potatoes, each with different water content but the same amount of flesh; they're different potatoes so obviously they have different masses, and that's the denominator unit of the (water content ratio) fraction in a sense.
I sort of agree, but also, especially under exam conditions, arriving at the (correct) answer I would definitely think 'well obviously I went wrong somewhere'.
Yeah, but the fact that it's a little tricky to think about, and that the trickiness doesn't come from the algebra part of the problem are exactly why I would say that's a terrible question to ask under exam conditions in the first place. I'd be totally cool with assigning it as homework, both because it could generate some meaningful discussion, and because doing the problem on one's own and with ample time to think gives the student the opportunity to work through the "paradoxical" aspects themselves.
A more relatable example to me is with chocolate bars.
A 85% chocolate has 3 times more sugar than a 95% chocolate.
I wonder the world-wide impact in people health if they advertised the ratio in terms of sugar instead of cacao.
Why are you assuming that leaving potatoes out overnight would change them from 99% water to 98%? Is your house directly adjacent to an active volcano? Why would you even measure that?
A section titled "The Language Paradox" was removed on October 2:
> Careful wording must be used to ensure that the "paradox" is correct.
With the explanation: "This is 100% original research, which as noted contains errors"
So the only thing that makes the "paradox" interesting is that it's badly worded, but any commentary to that effect is original research, so in the end we're just left with a fairly unremarkable riddle on Wikipedia and grumpy people like myself complaining about it.