## A Fun Math "Puzzle" [Solution]

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Internetmeme
Posts: 1405
Joined: Fri Jul 25, 2008 3:16 pm UTC
Location: South Carolina, USA

### A Fun Math "Puzzle" [Solution]

So, I was scrolling through the board today, and noticed this thread, where the OP posted an equation that seemed to have undeclared variables in it. A user pointed this out, and it was immediately closed for being nonsensical.

Image here:
Spoiler:

Since I don't want to find a host for an edited image, I'm going to just write stuff here:

Equation (1) Square/Pentagon/Hexagon (SPH) + SPH + SPH = 45
Equation (2) Banana Bunch (4) + Banana Bunch (4) + SPH = 23
Equation (3) Banana Bunch (4) + 3'oclock + 3'oclock = 10
Equation (4) 2o'clock + Banana Bunch (3) + Banana Bunch (3) + Pentagon/Hexagon = ??

At first, I thought this was going to be some interesting thing where each character would perhaps represent a different portion of base10. In Equation (2), two banana bunches and an SPH leads to 23. One banana bunch and two clocks leads to 10. So perhaps the banana bunches would indicate 10' s position, and the number of inscribed shapes would indicate the 1's position.

Then I realized it's a lot easier (and maybe dissapointing) than that: it's literally just one of those "Gotcha!" puzzles that appear on social media. Here's my solution to it:

In Equation (1), three SPH = 45. 45/3=15. If you count up the number of corners, we get 4 from the square, 5 from the pentagon, 6 from the hexagon...which adds up to 15. So, the "rule" for an inscribed shape is "count up the number of corners, and you have the number the shape represents."

Equation (2) introduces bananas. Their representation is the number of bananas in the bunch. 4 bananas per bunch, across two bunches is 8. Add 8 to the 15 from the SPH, and we get 23. Still self-consistent.

Equation (3) introduces clocks. And their value is just that of the clock face. 4 bananas + 3*2 = 10.

Using these rules, Equation (4) translates to 2 + 3 + 3*(5+6). Which equals 38 if you follow the standard order of operations.

It looks like the author decided to be clever in representing their system of numbers, and did the other "check to make sure they're paying attention at the bottom of the page" trick.
This last bit, the "Make sure they read the page" bit leads me to believe that the actual solution is the following:
Spoiler:
Sign your name on the page and ignore every other instruction.

That said, this type of puzzle is pretty horrible, because they're typically so horrendously vague that nearly *any* interpretation can be made-up for that "gotcha" aspect. A series of symbols is set up in the first three lines, the rules of which we're left to infer, but which we cannot confirm. If the OP wanted to make this puzzle better, adding three more equations allowing us to confirm the rules that are implied are what we think they are would be the proper way to go about it. As it stands, this is something I'd expect to see viral on a Facebook page with wild (and probably as well-founded as mine) conspiracy theories as to what each symbol means. Check back on the OP to see what I mean, with another user's (probably equally valid) interpretation of the puzzle.

Which is ultimately the problem that these sorts of viral puzzles have: they're deliberately vague with no real verifiable solution and intentionally open to debate to encourage people to "impress their friends" by solving and sharing them. It's the puzzle-equivalent of the "Share this with 10 people or a ghost will steal your socks from the dryer" chain letters you see going around.
Spoiler:

HES
Posts: 4886
Joined: Fri May 10, 2013 7:13 pm UTC
Location: England

### Re: A "Fun" Math "Puzzle" [Solution]

Internetmeme wrote:Which is ultimately the problem that these sorts of viral puzzles have: they're deliberately vague with no real verifiable solution and intentionally open to debate to encourage people to "impress their friends" by solving and sharing them. It's the puzzle-equivalent of the "Share this with 10 people or a ghost will steal your socks from the dryer" chain letters you see going around.

More to the point, debating the ambiguities = social media comments = wider audience. These BS "puzzles" only exist because they pander to facebook algorithms. Every single one deserves a chopped hand.
He/Him/His

Bloopy
Posts: 215
Joined: Wed May 04, 2011 9:16 am UTC
Location: New Zealand

### Re: A Fun Math "Puzzle" [Solution]

This particular one has been showing up on Facebook a lot in the last few months. Rather than testing maths, it mainly just tests whether people look closely enough at such an irritating post to notice that the symbols in the last line have been altered. I certainly didn't, and it just made it all the more irritating than usual.

In the context of these types of problems, I don't think this one is that ambiguous. Sure, it'd be a lot better to come across it in a book of puzzles that you actually want to look at for more than 5 seconds. But the idea of being unsatisfied with the '38' solution once you've got it begins to remind me of a certain pal of ours and his thoughts on assumptions.

On a related note, I made this joke math problem to post on Facebook. I've been meaning to make fun of the "which tank will fill first?" puzzles sometime too.

Spoiler: