Assuming that the amount of paint used is proportional to the surface area painted, and
assuming that she paints of 6 surfaces of the prism,
total surface area = 2( (2.5)(2.5) + (2.5)(3.6) + (2.5)(3.6) ) = ....
the area of the base = (2.5)^2 = ....
subtract the two answers
form the fraction: surface without bottom/total surface area
convert that to a percentage.
Let me know what you get
Enya is building a storage cupboard in the shape of a rectangular prism. The rectangular prism has a square base with side lengths of 2.5 feet and a height of 3.6 feet. Use percentage to compare the amount of paint she would use to paint all but the bottom surface of the prism to the amount she would use to paint the entire prism. Round your final answer to the nearest tenth.
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