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idnof
Apr 4, 2008, 08:34 AM
An indoor physical-fitness room consists of a rectangular region with a semicircle on each end . The perimeter of the room is to be a 200-meter running track. What measurements will produce a maximum area of the rectangle?

galactus
Apr 4, 2008, 03:34 PM
Do you have any other dimensions you forgot? Just checking.

The perimeter is P=2{\pi}r+2y=200; \;\ {\pi}r+y=100

The area is A=2ry+{\pi}r^{2}

You could solve P for y and sub into A, then differentiate, set to 0 and solve for r.