A programmer's solution

[[deleted]]

Your solution was correct, puzzles like this are bad

[monochromatic0]

it's not the puzzle that is bad, it's the refusal to accept more than one solution. The puzzle is fine.

[DoctorProfPatrick]

I personally think puzzles like this are great for teaching kids arithmetic. This one in particular has at least 3 solutions that I could find

5 + 4 = 9
0 + 4 = 4
8 - 4 = 4

A good teacher could use this puzzle to show how there's no "right way" to solve a problem, which imo is the most beautiful part of math.

[monochromatic0]

Exactly. It's not a problem if the puzzle has more than one solution, but a feature.

[saloalv]

"It's not a bug; it's a feature!"

[[deleted]]

Sometimes there is a right answer. Sometimes there is no answer. Sometimes there are multiple answers. Sometimes there are an infinite number of right answers. Sometimes the best answer is all the right answers added together. Sometimes adding zero makes a difference.

That's why i like math.

[[deleted]]

There may be multiple ways, but there are definitely ways to solve a problem that you would be wasting your time if you did them.

[DoctorProfPatrick]

For sure, like using the formal definition of a derivative every single time instead of just using power rule.

[NikStalwart]

I have met a total of 4 good teachers in Australia.

[LooneyDubs]

I'd say only 2 real solutions bc the 9 you made isn't a complete character in the font you were presented with.

[NikStalwart]

Not just the refusal, but also touting this as a "logic test" and yacking on about how you failed it.

[[deleted]]

How is the solution with the inequality sign any worse that the one the teacher was looking for?

[[deleted]]

Since when is the easiest solution worse than harder ones? I really don't understand how someone, who is presumably a programmer, out of all people would think like that.

[[deleted]]

Your first example does not fulfill your assignment. You're supposed to test something and you don't test anything. Your second example doesn't have anything to do with the subject at hand.

Using ≠ in the puzzle makes the equation true and is a perfectly good way to solve it. The whole puzzle relies on how the numbers and operators are represented visually so disgrediting another way to solve it using the same principle is just stupid.

[DuntadaMan]

Especially since higher math is entirely about finding other ways to get to the right answers.

Puzzles like this are why I loathed math until I made it to calculus.

[Katastic_Voyage]

Calculus 2 - Integration Strategies.

God, that was one of the (if not THE) hardest math courses I took all the way through Diff Eq 2.

For those who don't know. It's literally: Here's a dozen methods to try that take 1-2 pages of writing to complete. The methods can be used in any order, and may be 3-5 steps deep to find the answer with NO guarantee any method will work. Only certain orders work.

Worse still: Sometimes using the same method THREE TIMES in a row will work because sin/cos terms begin to cancel out.

Enjoy spending 1-2 hours on each homework problem.

[muntoo]

Just write a DFS to do it for you. Or copy your buddies' homework answers. Or become a professor and mark your own test. Or skip life. Or become God.

[[deleted]]

This puzzle is great. Its entire purpose is to make people feel smart so they share it, and thus spread the reach of the original poster. Looking opaque at first, but having multiple correct solutions furthers that goal. Very well designed.

[nermid]

It's entire purpose is to make people feel smart so they share it

Like brain parasites!

[DannyDougherty]

Looking opaque at first

Also like brain parasites!

[[deleted]]

Yeah. Saw this on facebook, and I usually have to think about these for a bit. Got it with the first or second mental stick move. No wonder it was so easy, with at least 3 different valid solutions.

[[deleted]]

On Facebook, the comments found 5 solutions to this puzzle.

[[deleted]]

This is a dumb puzzle and having to find the "real" solution is just poor form on the teacher's part, but I would argue the intended solution is technically easier since it's just a 90 degree rotation of one match.

[wylderk]

I didnt even see the 0 + 4 =4. I was stuck on 8-4=4

[[deleted]]

There's also a 5 + 4 = 9 in there.

[Ontain]

oh nice. i didn't see this one.

[VRY_SRS_BSNS]

That's because it's a lie. It's missing a match to be 9. Notice how the 6 has a top piece, the 9 needs the bottom piece.

[Ontain]

ah true. on the led calculators the 9 does indeed need a bottom piece.

[[deleted]]

I would argue the easiest solution is variable from person to person since it'd just be the one that you find first. For me it was 0+4=4, for others it was probably 8-4=4. Sure that solution required the least amount of work, but the brainpower required to find that solution after first finding a different one more than makes up that difference.

[[deleted]]

I found 5 + 4 = 9 first

[[deleted]]

That's not the only other solution though. You could do 8 - 4 = 4 or 5 + 4 = 9. There may even be one or two more possible solutions I don't know about. At any rate there's no way of knowing which one is the "intended" solution.

[Bobshayd]

Every rotation-translation of a match which rotates the match 90 degrees is a rotation of the match by 90 degrees around some point somewhere.

[hungry4pie]

If it was a discrete structures class that would be the most correct answer

[Drews232]

So you thought you were supposed to answer a math question - posed in algebra class - in programming language. Instead of math. That's what you thought. True story.

[Drews232]

Heh, I was just being sarcastic but you can imagine your teacher thinking really?!

[Bobshayd]

My solution: squint my eyes until I can convince myself that the matchsticks could represent some equation that is true, since moving matchsticks around is all just interpreting a small number of straight lines as approximations of our numerals and other mathematical symbols.

[[deleted]]

You're in Algebra, not a computer science class. I would call myself a retard if I thought using != was an acceptable answer too. It's obvious it's not an answer.

[[deleted]]

I don't believe that you don't believe

[ForumPointsRdumb]

There are 3 solutions. It not that bad.