Question

Find the surface area of a sphere if the circumference of a great circle is 43.96 centimeters. Use 3.14 for p. Round to the nearest tenth.

Answer 1

Circumference = 43.96 cm, find radius:

Circumference = 2πr

43.96 = 2(3.14)r

43.96 = 6.28r

r = 43.96 ÷ 6.28 = 7 cm

We found out that the radius is 7 cm, find surface area:

Surface area = 4πr² = 4 (3.14) (7)² = 615.4 cm² (nearest tenth)

Answer: 615.4 cm²