Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
Drexel University or The Math Forum.



Re: geometry
Posted:
Apr 29, 2004 1:14 AM


On 14 Apr 04 00:02:17 0400 (EDT), michael wrote: >construct a circular target with nine regions of equalarea, with one a >circle in the middle and spokes going out to the edge. if the whole >circle is 6 feet in diameter, what will the diameter of the inner >circle be?
R = 3 ft is the target radius r is the radius of the inner circle
Area of the inner circle: A(C) = ÃÂ¶rÃÂ²
Area of each spoke region (8 of them): A(S) = (ÃÂ¶RÃÂ²  ÃÂ¶rÃÂ²)/8
The area of each spoke region is equal to the area of the inner circle: A(S) = A(C)
(ÃÂ¶RÃÂ²  ÃÂ¶rÃÂ²)/8 = ÃÂ¶rÃÂ² RÃÂ² = 9rÃÂ² R = 3r r = R/3 = 3/3 = 1 ft
Diameter of the inner circle: d = 2r = 2 ft



