The Solution:
Given:
We are required to find the amount it will cost to make 600 of the above boxes if cardboard cost $0.05 per square inch.
Step 1:
Find the surface area of the box.
[tex]Total\text{ surface area}=2(L_1\times W_1)+2(L_2\times W_2)+2(L_3\times W_3)[/tex]In this case,
[tex]\begin{gathered} L_1=8in. \\ W_1=12in. \\ \\ L_2=3\imaginaryI n \\ W_2=12\imaginaryI n \\ \\ L_3=3\imaginaryI n \\ W_3=8\imaginaryI n \end{gathered}[/tex]Substituting these values in the formula, we get:
[tex]TSA=2(8\times12)+2(3\times12)+2(3\times8)[/tex][tex]TSA=2(96+36+24)=2\times156=312\text{ }in.^2[/tex]Step 2:
Find the cost of one box.
[tex]\begin{gathered} 1in^2=\text{\$0.05} \\ So, \\ 312in.^2=312\times0.05=\text{ \$15.60} \end{gathered}[/tex]Step 3:
Find the cost of 600 boxes.
[tex]\begin{gathered} 1\text{ box}=\text{ \$}15.60 \\ So, \\ 600\text{ boxes}=600\times15.60=\text{\$9360} \end{gathered}[/tex]Therefore, the correct answer is $9360.