What is 5 equal to?

Can you find what corresponds to 5?

If: $$1=5$$ $$2=6$$ $$3=7$$ $$4=8$$

then, $$5=?$$

Note: the answer is not 9.

9 Answers

Is the answer simply

1, due to symmetry (thanks for the correction, @Peter!!) of the equals sign?

• Why are my puzzles so easy for you?! Sep 11, 2018 at 11:50
• @WaisKamal Because El is short for Elite :D Sep 11, 2018 at 11:56
• @user477343 good point! Sep 11, 2018 at 12:00
• I think you mean symmetry, instead of commutativity. Sep 11, 2018 at 15:20
• Thanks @Peter, that I do. Will credit you and update the answer! Sep 11, 2018 at 15:31

It is:

? (question mark), that's by definition.

• Good thinking! (though not the right answer) Sep 11, 2018 at 11:50
• I don't mind downvoting but what is wrong with my answer to make you do that? Sep 11, 2018 at 11:57

22, using the OEIS sequence A098670

or literally,

not 9.

• I don't understand that sequence. The $a(n)$'th digit of WHAT is a 2? Is there something missing in the description? Sep 11, 2018 at 15:20
• @Vincent - the $a(n)$'th digit of the sequence itself. The sequence starts with 5, must be growing as slow as possible, and (since it starts with 5) its 5th digit must be 2. Hence 5, 6, 7, 8, 22... work from there.
– Neo
Sep 11, 2018 at 15:53

Well, since the first equation says:
1 = 5
I would say the solution is:
5 = 1

• Damn, @El-Guest got there first, buddy. That rule is lame, in my opinion. This is about puzzling, not some kind of competition :\ Sep 11, 2018 at 11:47
• Oh, shame on me :( Sep 11, 2018 at 11:49
• Correct answer but as stated by @user477343, El-Guest answered first. I will upvote all answers, but accept the one that came first. Sep 11, 2018 at 11:52

its-

1, assuming $=$ signs work as they normally do, if $1=5$ then $5=1$ would be true

• El-Guest got it first Sep 11, 2018 at 11:54

It is

13. Replacing 5 with 1+4 or 2+3 and substituting those numbers from the given list, we find 5+8 or 6+7. Both equal 13.

For mathematicians, it could be :

$5=1$

Because,

$n_1 = n_2 [5] + 1$

As a result :

$1 = 5[5] + 1 = 0 + 1$

As well as

$2 = 6[5] + 1 = 1 + 1$

And

$4 = 4[5] + 1 = 3 + 1$

Finally :

$5 = 5[5] + 1 = 1$

Using :

As,
1 = 5

So,
5 = 1
Note: the answer is not 9.

1 = 5
Therefore, 5 = 1
That would not be true if polynomial of certain degree was given.

• Welcome to puzzling.SE! Not bad, but this is basically what the accepted answer is saying. Sep 13, 2018 at 9:27