Math
posted by Anonymous on .
What is the approximate surface area of the sphere? C= 37.68 km

C = pi * d
37.68 = 3.14 * d
37.68 / 3.14 = d
12 = d
_____________________________
Surface Area of a Sphere = 4 pi r 2
A = 4 * 3.14 * 6^2 
Circumference :
C = 2 r pi
C = 2 r pi Divide both sides by 2 pi
C / 2 pi = r
r = C / 2 pi
r = 37.68 / ( 2 * 3.14 =
r = 37.68 / 6.28
r = 6 cm
Area:
A = 4 r ^ 2 pi
A = 4 * 6 ^ 2 * pi
A = 4 * 36 * pi
A = 144 pi
A = 144 * 3.14
A = 452.16 cm ^ 2 
The area equals 452.16.