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Jens
2009-Nov-13, 06:27 AM
I have a simple but somewhat cryptic math question. Suppose I have a thousand circles of equal diameter, say each circle is of diameter x. Now, how would I find the sum total of their circumferences?

I'll try to avoid making any more posts for a little while, but I'd be grateful for any suggestions. :)

Nick Theodorakis
2009-Nov-13, 06:38 AM
Circumference of a circle is just pi times the diameter, so pi*x for one circle, thus 1000*pi*x for the total. Unless this is some trick question I'm not seeing through.

Nick

Tobin Dax
2009-Nov-13, 06:39 AM
Am I missing something? You can calculate the circumference of each from the diameter, and you know how many circles you have. I don't quite see the cryptic part. (Well, maybe I do since my students didn't quite answer this question on their own earlier today.)

jfribrg
2009-Nov-13, 08:10 PM
the answer is kilopi, which Jens has justs achieved. Congrats.

Perikles
2009-Nov-13, 08:23 PM
the answer is kilopi, which Jens has justs achieved. Congrats.Well, it's x times kilopi, but congrats all the same.

Nick Theodorakis
2009-Nov-13, 08:27 PM
D'Oh!

Congrats, Jens.

Nick

Tobin Dax
2009-Nov-13, 09:18 PM
D'Oh!

Congrats, Jens.

Nick
What he said (except sign it with my name).

ETA: I probably would have got it if Jens' circles were of unit radius.

kleindoofy
2009-Nov-13, 09:25 PM
Hmmm, if one placed all of the circles exactly on top of one another and observed the stack from above, the total circumferences of the thousand would be equal to the circumference of only one of them, reducing the order to an establishment. ;)

Jens
2009-Nov-14, 09:45 AM
Thanks everyone. I was kind of looking forward to posting that for a while, so I tried to keep on the alert to make sure I didn't unintentionally post the 3142nd post somewhere else. And yes, I guess I should have said of radius 1 rather than x.

Do I get a light saber or is that a different order? :)

Tobin Dax
2009-Nov-14, 06:38 PM
Thanks everyone. I was kind of looking forward to posting that for a while, so I tried to keep on the alert to make sure I didn't unintentionally post the 3142nd post somewhere else. And yes, I guess I should have said of radius 1 rather than x.
Pff. Don't take me seriously. I obviously wasn't paying enough attention.

Do I get a light saber or is that a different order? :)
Only in pink, if you want it now. The rest are on back order. I've been waiting months for mine. :mad:

Fiery Phoenix
2009-Nov-14, 07:56 PM
LOL! That was an AWESOME trick, Jens! Too bad I came in too late.

Also, you can laugh at me all you want, but I just realized what 'kilopi' actually means. xD

peter eldergill
2009-Nov-14, 08:25 PM
the answer is kilopi, which Jens has justs achieved. Congrats.

Ohhhh...a wise, guy, eh? I'll have to start thinking of ways to get back at him for that trick :)

Nah....too much work, but now at least I know what Kilopi is :shifty:

Pete

slang
2009-Nov-15, 01:53 AM
Thanks everyone. I was kind of looking forward to posting that for a while, so I tried to keep on the alert to make sure I didn't unintentionally post the 3142nd post somewhere else. And yes, I guess I should have said of radius 1 rather than x.

Very, very subtle. Love it! Congrats :)

Jens
2009-Nov-15, 08:30 AM
Ohhhh...a wise, guy, eh? I'll have to start thinking of ways to get back at him for that trick :)

Nah....too much work, but now at least I know what Kilopi is :shifty:

Yeah, I realize there's a fine line between clever and being a wise guy. I think it was kind of borderline, but it was too cute to resist. I also still remember being confused the first time I heard the term "kilopi" on this board. It didn't occur to me that the past part was pronounced "pie" rather than "pee".

hhEb09'1
2009-Nov-15, 08:50 AM
Congrats, Jens, here's fireworks (http://apod.nasa.gov/apod/ap091113.html) and a calliope (http://en.wikipedia.org/wiki/Calliope_(music)) (note spelling) :)

DonM435
2009-Nov-18, 03:57 AM
Congratulations.

I'm presently building up my number at the speed of a mollusk. You might say that the best that I can aspire to is Order of Octopi.

jfribrg
2009-Nov-18, 12:33 PM
Congratulations.

I'm presently building up my number at the speed of a mollusk. You might say that the best that I can aspire to is Order of Octopi.

And I thought that my crawl to kilopi was slow. I sure could use those 100 posts that I lost when the BABB merged with UT.