Question

Find the radius of a sphere with a surface area of 804 cm^2.

A. 9cm
B. 8cm
C. 64cm
D. 204cm

Answer 1

Surface area of sphere equals its four radii squared multiplied by the number π.
We have then:
A = 4 * π * R ^ 2
Substituting:
804 = 4 * π * R ^ 2
Clearing the value of R we have:
R = root (804 / (4 * π))
R = 7.99876785 cm
Nearest whole number:
R = 8 cm
Answer:
The radius of a sphere is:
B. 8cm