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Math Puzzle

Can you solve it?

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#26 Blue

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Posted 02 February 2009 - 10:32 PM

.41990568915769
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#27 TantumBull

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Posted 02 February 2009 - 10:35 PM

.414...........

My CAD software only displays 3 decimal points. Yes, I'm a cheater. N34, you're right.
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#28 imaseoulman

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Posted 02 February 2009 - 10:39 PM

N34 is right, but the question is...Why?
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#29 Zorns Lemma

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Posted 02 February 2009 - 10:41 PM

Huzzah!

Took me two tries. The first one I did something wrong with division and ended up with 1/2, which by simple estimation is obviously wrong.

Total time was less than ten minutes.

Edited by Zorn's Lemma, 02 February 2009 - 10:41 PM.

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#30 TantumBull

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Posted 02 February 2009 - 10:48 PM

I have no idea how to do this. And I should know because we're studying circle theorems in trig right now. Damn this is frustrating!
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#31 Zorns Lemma

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Posted 02 February 2009 - 10:53 PM

You don't need trig for it.

Also, Just Some Bob, way to spoil it for everyone who's yet to solve it.
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"In short, the same knowledge that underlies the ability to produce correct judgement is also the knowledge that underlies the ability to recognize correct judgement. To lack the former is to be deficient in the latter."
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#32 imaseoulman

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Posted 02 February 2009 - 10:55 PM

JSB and Zorn both got it faster than I did.
Splitlip, I think you're still off with your math, but your method should work.
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#33 Split

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Posted 02 February 2009 - 10:58 PM

Fucking hell. Thanks for the problem. Props bob, I took a really long way around that. I've managed to get really bad at simplifying, somewhere along the line I missed a divide by two. Mind posting or PM'ing the forum name? I'd love to get to work on stuff like this some more.
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Teehee.

#34 umpshaplapa

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Posted 02 February 2009 - 10:59 PM

Fuck. This is exactly what I'm learning in school, and I have no idea.

EDIT- is the cirmcumfrence of the smaller circle 1/8th of the larger circle? That would help.

Edited by umpshaplapa, 02 February 2009 - 11:01 PM.

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QUOTE(Talio @ Jun 29 2009, 01:50 PM) View Post

i got a black belt in noob banning in 2004.


#35 imaseoulman

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Posted 02 February 2009 - 11:00 PM

What forum? I was trying to figure out the ideal OD of a barrel and realized I had a cool math puzzle (after I realized it could be easily solved with calculus). My solution uses the same idea as JSB's (pythagorean theorem) but I used a different diagonal. JSB's seems more intuitive now that I look at it.
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#36 oodalumps

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Posted 02 February 2009 - 11:03 PM

deleted

Edited by oodalumps, 02 February 2009 - 11:22 PM.

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#37 Ubermensch

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Posted 02 February 2009 - 11:07 PM

Pardon my 14-year-old math stupidity, but couldn't one simply find the proportion of the smaller circle to the larger circle, then divide to get the radius of the smaller circle?
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#38 Split

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Posted 02 February 2009 - 11:15 PM

So, I asked this question as part of a puzzle challenge on a different forum...
... So here's the question copied from the other forum:


That forum.

Pardon my 14-year-old math stupidity, but couldn't one simply find the proportion of the smaller circle to the larger circle, then divide to get the radius of the smaller circle?

That proportion (assuming you mean circumference or area) isn't very simple without calculus.

ooda, you're right, but mind keeping the answer to yourself so it doesn't get spoiled for others?
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Teehee.

#39 imaseoulman

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Posted 02 February 2009 - 11:20 PM

Yes, ooda, please take that down.

The other forum is a magic trick related site...so...not really relevant unless you want to be a magician (which is just about as fun as NERF wars, if you ask me).
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#40 Ubermensch

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Posted 02 February 2009 - 11:24 PM

Why wouldn't it be simple? Say the proportion of the area/circumference of the smaller circle to the larger one is (I'm just throwing out random numbers):

3.413:1

Find the radius of the larger circle (it is assumed to be 1), then divide by 3.413. Then you have the radius of the smaller circle.
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#41 darthmonkey

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Posted 03 February 2009 - 01:29 AM

The ratio is 1 / (sqrt(2) + 1).

Though, I don't see how you could get this without remembering to apply the Pythagorean theorem, which definitely is more than deduction.
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#42 Rambo

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Posted 03 February 2009 - 01:12 PM

Fucking hell. Thanks for the problem. Props bob, I took a really long way around that. I've managed to get really bad at simplifying, somewhere along the line I missed a divide by two. Mind posting or PM'ing the forum name? I'd love to get to work on stuff like this some more.


As much as I hate helping you out I think you and others would like this site and its accompanying forum.
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#43 nerfer34

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Posted 03 February 2009 - 02:28 PM

Wooo... I got it right in under 2 minutes!

Nope, i didn't cheat. I just figured that the answer had to be some number that I've heard of since only the radius was given. Then I remember for something in math we used the square root of two. So I just subracted the radius(1) from suare root of 2.

And I get C's in honors math in high school, I'm really not that smart. Just street smart.
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#44 MoonMaster

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Posted 03 February 2009 - 04:03 PM

Seeing as Nerfer34 just posted a much simpler way, my way seems retarded now. I used the formula <Removed due to spoiler> where x is the radius of the small circle. I am pretty sure that this is correct, but I want someone else to verify. I will remove the formula if it is considered a spoiler.

There. Thanks Splitlip, It is now spoiler free.

Edited by MoonMaster, 03 February 2009 - 06:30 PM.

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5. Protip: sarcasm is good for making someone else look like more of an idiot than they already do. However, if you are an idiot to start with, using sarcasm just makes you look like a COLOSSAL idiot.


#45 Split

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Posted 03 February 2009 - 04:50 PM

It's correct, and he is asking people to remove spoilers like that.
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Teehee.

#46 Talio

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Posted 03 February 2009 - 05:40 PM

It's my opinion that this was his homework and he just got you saps to do it for him. I'm going to start posting some system troubleshooting challanges.
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#47 NerfMonkey

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Posted 03 February 2009 - 06:54 PM

I was on the right track when I lost patience and gave up. I think I understand why it's the square root of 2. It has to do with isosceles triangles but I won't say any more for fear of spoiling it.

Edited by NerfMonkey, 03 February 2009 - 07:12 PM.

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#48 imaseoulman

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Posted 03 February 2009 - 08:13 PM

It's my opinion that this was his homework and he just got you saps to do it for him. I'm going to start posting some system troubleshooting challanges.

That would be pretty funny. However, since I'm not currently enrolled in any sort of course, nor do I have job that requires any thinking whatsoever, that is unlikely. But, I do like the idea of posting system troubleshooting challenges. I'd be up for it.
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#49 nerfer34

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Posted 03 February 2009 - 08:24 PM

Hahaha, I don't unserstand why everyone thinks telling the answer is spoiling. If the person trying the problem really didn't want to know the answer then he really shouldn't be looking at page 3 or 4 of the thread.
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#50 zombiegaara

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Posted 03 February 2009 - 08:25 PM

i'm gessing since it is in 1/4 of the circle. the circle being 1, the smaller green circle should be 0.25. just a geuss.
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