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Circle Areas

Bert Bates

Joined: Oct 14, 2002
Posts: 8803
Imagine a circle:
Now imagine a square inside the circle, such that all four of the square's corners touch the edge of the circle (inscribed).
Now imagine a second circle inside the square,such that the inner circle touches the square at all four of the square's midpoints (inscribed).
What's the ratio of areas of the two circles?

Spot false dilemmas now, ask me how!
(If you're not on the edge, you're taking up too much room.)
Joel McNary

Joined: Aug 20, 2001
Posts: 1817

I get 2:1
If the square has a length of 2x, then the inner circle has a radius of x and the outer circle a radius of x*sqrt(2). Apply A = PI * r^2 to each circle, and you get areas of PI * x^2 and * PI * x^2, respectively. Reduce (and express in terms of larger:smaller), and you get 2:1.
[ November 16, 2003: Message edited by: Joel McNary ]

Piscis Babelis est parvus, flavus, et hiridicus, et est probabiliter insolitissima raritas in toto mundo.
Bert Bates

Joined: Oct 14, 2002
Posts: 8803
I guess I'm gonna have to make these a bit harder...
I agree. Here's the link:
subject: Circle Areas
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