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11:06
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Q: how do I find all real pairs of a,b such that (80+b)/(10a+b) is an integer?

bobjeff123 how do I find all real pairs of a,b such that (80+b)/(10a+b) is an integer? I tried using the Euclidean algorithm and I ran it with 80+b and 10a+b once assuming 80+b>10a+b but then I didn't know what to do. So how should I do this problem?

@coffeemath thank you I edited the mistake
Have you seen the advice on how to ask a good question?
@JohnOmielan Im not sure if my approach was right but yes its real numbers
If you don't have any idea how to start, see what you can add to the question body here.
@TobyMak what are some things I could improve on for this post? Thanks
11:06
@bobjeff123 Rather than working on the Euclidean algorithm as it might get messy with two variables, where does this problem come from? This will form the context of the question which makes it easier for us to answer.
hello
so the question comes indirectly from crossword from a competition, and when I read the answer for the crossword it seemed to have used trial and error which I thought was inefficient so I set up an equation for it
That's great!
Then you can show us the original crossword and then yeah, mention that you didn't want to use trial and error
I actually get how to solve the crossword, it was just that small obstacle and technically I could use trial and error like the solution but I'm more interested in how to find a solution for that equation I just came across. The crossword is sort of just random inspiration, it's also from a UK competition which I don't think expects you to know the theory to solve this problem.
11:13
Well, the background of the equation is equally as important as the question itself.
How do I send it to you?
If you can say where the question comes from, then you will have a complete question.
@bobjeff123 Press "edit" on your question
And then you can add the details in
So I just add in where I got the inspiration for the problem?
11:17
Yeah
You can copy and paste what you said to me in chat if you want
I apologize for butting in, but it would be best if you could post a picture of all the relevant parts. Please also make sure that the problem is not part of an ongoing competition ( I am saying this because you mentioned a competition).
It was a couple of years ago, thats how I can get access to the answers
Yep, don't worry if you can't post the image (it will show up as an Imgur link)
11:22
do I post a picture of the crossword itself? Because I'm just saying I got inspiration for the question from that crossword however I don't really need to solve it
*it, is in the crossword
Post the picture of the crossword
Do I take a picture?
and scan it?
Yeah
You can try using CamScanner or similar
as long as it's clear enough to be read
The images should have an Imgur link
Can you see the images I edited it now?
that is the crowssword
Yeah
It would help to fill in the other boxes that you got
11:30
I have already filled some
So what are they?
basically the number 5 tile can either be 8,5 or 2 but I'm just assuming its 8, and then Im setting the tile on the right to be "b" and the tile on the 4 to be "a". So I basically get 10a+b has to be a proper factor of 80+b so thats how I was inspired.
I also mean the other tiles such as the ones for 1, 2, and 3
The other tiles do not affect the 4 and 5 tiles, as in I don't care that much about the crossword itself. That was just inspiration for the problem, i
im more interested in the equation
If you just want the answer, this site is not designed for that
Rather it's supposed to be a collection of knowledge in mathematics, so that's how the context and the background play an important role
Plus, the way you are currently approaching the question might not be the best method to solve your problem
11:38
I do not just want the answer, I am interested in the process, the elegancy, and the techniques involved
Alright then, good to know
@TobyMak That may be the case, but - Im more interested in the equation rather than the crossword
"The XY problem is asking about your attempted solution rather than your actual problem.

That is, you are trying to solve problem X, and you think solution Y would work, but instead of asking about X when you run into trouble, you ask about Y."
Sorry I dont really get what that means, do I have to follow these rules when I post questions or something?
Basically, add as much information as you can to the question
I think you're holding back because you don't think the information about the crossword is related, but it actually helps us understand you better
As we can't read your mind after all
11:47
I just fell like talking too much about the origins/crossword may digress the question off topic as the solution is actually a bit long - after all equation is the main question here, should I instead mention what was going through my thought process when solving the problem so that people can understand my logical reasoning better?
Yes, that will do as well
Also, if you have the solution already, you can self-answer your question
You're probably tired of posting another image right now, but in future you can always self-answer your own questions.
I have the solution for the crossword only, in fact in an attempt to turn brute-force into efficiency, I feel as if it has turned into an overcomplication. But a good overcomplication; which was turned into an interesting problem for myself
12:03
In that case, Puzzling SE should be a better fit for your question

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