SOLUTION: A rectangular prism has sides that are in the ratio of 3:5:9. If the volume of the prism is 8640 cm^3, then what is the surface area of the prism, in square millimeters?

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Question 1114432: A rectangular prism has sides that are in the ratio of 3:5:9. If the volume of the prism is 8640 cm^3, then what is the surface area of the prism, in square millimeters?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
%283x%29%285x%29%289x%29=8640
x%5E3=64
x=4
So the width, height, and length are,
W=3%2A4=12
H=5%2A4=20
L=9%2A4=36
The surface area of the prism is,
SA=2%2AL%2AH%2B2%2AL%2AW%2B2%2AW%2AH
SA=2%2A36%2A20%2B2%2A36%2A12%2B2%2A12%2A20
Work that out for the answer in mm%5E2