Question:
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
Rob

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.

Penny

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