Question

If the diameter of a regulation size basketball is 9.4 inches, what is the surface area? Round to the nearest tenth.

A.59.1 in²
B.69.4 in²
C.88.4 in²
D.277.6 in²

Answer 1

Given,

Diameter of the basketball = 9.4 inches
∴ Radius of the basketball = diameter ÷ 2 = 9.4 ÷ 2 = 4.7 inches
π = 3.14159

Surface area of the basketball is the surface area of the sphere = 4 π r² = 4 × 3.141 x 4.7² = 277.59 = 277.6 inches²

Answer 2

SA=4pir^2
d/2=r
9.4/2=r=4.7

SA=4*3.141592*4.7^2
SA=227.591

answer is D