Given:
The shape of box is a right triangular prism.
Paper cost = 2 cents per square centimeter
To find:
The cost to cover the entire box.
Solution:
In the given right triangular prism, we have 3 rectangle surfaces and 2 triangular surfaces.
Area of a rectangle is
[tex]Area=length\times width[/tex]
Area of rectangle with length 4 cm and width 3 cm is
[tex]A_1=4\times 3=12\text{ cm}^2[/tex]
Area of rectangle with length 4 cm and width 4 cm is
[tex]A_2=4\times 4=16\text{ cm}^2[/tex]
Area of rectangle with length 4 cm and width 5 cm is
[tex]A_3=4\times 5=20\text{ cm}^2[/tex]
Area of a triangle is
[tex]Area=\dfrac{1}{2}\times base\times height[/tex]
Area of triangle with base 3 cm and height 4 cm is
[tex]A_4=\dfrac{1}{2}\times 3\times 4[/tex]
[tex]A_4=\dfrac{12}{2}[/tex]
[tex]A_4=6\text{ cm}^2[/tex]
Bottom and top triangular surfaces are equal.
[tex]A_5=A_4=6\text{ cm}^2[/tex]
Now, total surface area of the box is
[tex]A=A_1+A_2+A_3+A_4+A_5[/tex]
[tex]A=12+16+20+6+6[/tex]
[tex]A=60\text{ cm}^2[/tex]
Paper cost = 2 cents per square centimeter
Cost of 60 square centimeter paper is
[tex]60\times 2=120\text{ cents}[/tex]
Therefore, the cost to cover the entire box is 120 cents or $1.2.
