Given:
Concrete skateboard ramp has the shape of a triangular prism.
Base = 4 ft
Height = 4 ft
Length = 9.4 ft
Cost of concrete per cubic foot = $3.00
To find:
The volume of the triangular prism and the value of the concrete used in the ramp.
Solution:
Volume of triangular prism:
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
The volume of the triangular prism is 75.2 ft³.
Cost of concrete per cubic foot = $3.00
Cost of concrete for 75.2 cubic feet = 75.2 × 3.00
= 225.6
The value of the concrete used in the ramp is $225.6.