Question 886228: The edge of a cube. is 80cm long .How its volume and surface area i change if the egde is decreased by 10%?
Answer by JulietG(1812)   (Show Source):
You can put this solution on YOUR website! The volume of a cube is found by 
The volume of a cube with an 80cm long side is equal to  . 80 x 80 x 80 = 512000
If you decrease its side by 10%, you now have a cube with a 72cm side.
 , or 72 x 72 x 72 = 373248 cubic cm
By decreasing the side, you have decreased the volume by 512000-373248=138752, or 27.1%
.
The surface area of a cube is found by 
The surface area of a cube with an 80cm side is equal to 6* , or 6*6400, or 38400 sq cm.
If you decrease its side by 10%, it becomes 6* , or 6*5184, or 31104.
The decrease is 7296, which is 19%.
|
|
|
