Question 886228
The volume of a cube is found by {{{s^3}}}
The volume of a cube with an 80cm long side is equal to {{{80^3}}}.  80 x 80 x 80 = 512000
If you decrease its side by 10%, you now have a cube with a 72cm side.
{{{72^3}}}, 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%
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The surface area of a cube is found by {{{6s^2}}}
The surface area of a cube with an 80cm side is equal to 6*{{{80^2}}}, or 6*6400, or 38400 sq cm.
If you decrease its side by 10%, it becomes 6*{{{72^2}}}, or 6*5184, or 31104.
The decrease is 7296, which is 19%.