Quandaries and Queries


I have a shere with a circumference of 12 feet.
What is the total surface area of the shere in square feet and how did you find it?

Thank you



Hi Rob,

By the circumference of a sphere I assume you mean around the equator.

The circumference of a circle is 2 pi times the radius and hence you have

12 = 2 pi r

where r is the rddius. Thus the radius is

r = 6/pi

The surface area of a sphere is 4 pi times the square of the radius, and hence the area is

A = 4 pi r2 = 4 pi 6/pi)2 144/pi

which is approximately 45.84 square feet.



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