Question 212901
A compact disk has a diameter of 11.8 cm. What is the surface area of the disk in square centimeters? In square meters?


Step 1.  The surface area is given as 


Surface area = pi * (radius)^2 = pi * (diameter/2)^2 = pi * (diameter)^2/4


Step 2.  Let S = surface area, d= diameter and pi=3.14159


Step 3.  S = pi * (11.8)^2/4 = 109.4 cm^2  (Answer in square centimeters)


Step 4.  Since 1 m = 100 cm, then   


(1 m)^2 = (100 cm)^2 = 10000 cm^2


Step 5.  (109. cm^2)(1 m^2)/10000 cm^2)= (1.09/100) m^2 = 0.0109 m^2 (Answer in square meters)



I hope the above steps were helpful.


For Step-By-Step free videos in Introduction to Algebra, please visit 

http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry visit 

http://www.FreedomUniversity.TV/courses/Trigonometry.


Good luck in your studies!


Respectfully,
Dr J