#Find all b's <= 100 such that there exists an a natural number s.t. [100*a/b] = 314

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cold hinge
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How can you find all b's <= 100 natural numbers such that there exists an a s.t. floor(100 * a/b) = 314?

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mystic vapor
cold hinge
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That is the original problem

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It was question number 1 on my number theory exam

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And I had no idea on how to approach this problem

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Let me repeat myself:

Find all "b" non-zero natural numbers <= 100 such that there exists an "a" natural number floor(100*a/b) = 314

mystic vapor
cold hinge
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Am I misunderstanding but what do you mean by original text then?

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Like a picture of my exam?

mystic vapor
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Yes, exactly.

cold hinge
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Anyway

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Thanks for taking your time to think on this problem

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A first observation is that for b = 1,2 4, 5, 10, 20 ,25 there does NOT exist an a

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So these number are already out from the start

mystic vapor
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Strictly speaking there's infinitely many b's.

cold hinge
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b non-zero natural numbers <= 100

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There are exactly 100 b's to check

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?

mystic vapor
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...what?

mystic vapor
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That's one of many reasons why I prefer photos of original text.

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I don't mean to be rude about it, but like, it's very important to state the problem clearly and exactly.

cold hinge
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How many of the 1, 2, 3, ..., 100 there exist an a such that floor(100*a/b) = 314

mystic vapor
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That's not even grammatically correct, but setting that aside

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What does the floor function do?

cold hinge
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Take to the nearest integer below it

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Takes *

mystic vapor
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Therefore, if floor(100a/b) = 314, what can we say?

cold hinge
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314 <= 100a/b < 315

mystic vapor
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Therefore?

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...therefore: 314b <= 100a < 315b 0 <= 100a - 314b < b

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@cold hinge Recognize the middle term there?

cold hinge
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Bezout?

mystic vapor
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Right. And what's that?

cold hinge
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Hold up

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On the toiley

mystic vapor
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...you don't have to tell me that.

cold hinge
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Too late

mystic vapor
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It's not too late to apologize and yet you haven't.

cold hinge
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Alright

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Forgive me

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I wasn't able to type when I had 2 use both hands with my diarheatic situation

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With that out of the way

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Lets focus on the problem again, shall we?

mystic vapor
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Why did you tell me more?

cold hinge
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Too late

mystic vapor
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It's not too late for me to stop helping you.

cold hinge
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True

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Sorry

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Back to the problem

mystic vapor
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It's hard to believe you when that's not your first reaction.

cold hinge
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True

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Can't deny your observation

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Back to the problem

mystic vapor
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Yes, you go back to your problem, and I go somewhere else.

cold hinge
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Damn

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Thought my apology was good

mystic vapor
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Too late.

cold hinge
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Haha

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Nah but seriously now

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How does Bezout work with the inequality?

mystic vapor
cold hinge
mystic vapor
cold hinge
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?

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Ah no my mistake

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Thats just my dialect

mystic vapor
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That's not how a dialect works.

cold hinge
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Its seems to have been a language barrier

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Didnt realize the mood wasnt for it

mystic vapor
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How in the hell could you possibly not realize that?

cold hinge
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+close

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# cold hinge +close
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