Select the correct answer.

A storage bin is built as a rectangular prism with a closed top. The length is 3.5 feet, the width is 2 feet, and the height is 2.5 feet. What is the amount of material needed to make the box?

A. [tex]41.5 \, \text{ft}^2[/tex]

B. [tex]34.5 \, \text{ft}^2[/tex]

C. [tex]36.5 \, \text{ft}^2[/tex]

D. [tex]17.5 \, \text{ft}^2[/tex]



Answer :

To determine the amount of material needed to build the storage bin, we should calculate the surface area of the rectangular prism (also known as a rectangular box).

A rectangular prism has six faces:
- There are two identical faces for each pair of dimensions: length × width, width × height, and length × height.

1. Calculate the area of the two faces with dimensions length and width:
[tex]\[ \text{Area}_{\text{length × width}} = 2 \times (3.5 \, \text{ft} \times 2 \, \text{ft}) = 2 \times 7 \, \text{ft}^2 = 14 \, \text{ft}^2 \][/tex]

2. Calculate the area of the two faces with dimensions width and height:
[tex]\[ \text{Area}_{\text{width × height}} = 2 \times (2 \, \text{ft} \times 2.5 \, \text{ft}) = 2 \times 5 \, \text{ft}^2 = 10 \, \text{ft}^2 \][/tex]

3. Calculate the area of the two faces with dimensions length and height:
[tex]\[ \text{Area}_{\text{length × height}} = 2 \times (3.5 \, \text{ft} \times 2.5 \, \text{ft}) = 2 \times 8.75 \, \text{ft}^2 = 17.5 \, \text{ft}^2 \][/tex]

4. Sum all these areas to get the total material needed:
[tex]\[ \text{Total material needed} = 14 \, \text{ft}^2 + 10 \, \text{ft}^2 + 17.5 \, \text{ft}^2 = 41.5 \, \text{ft}^2 \][/tex]

Therefore, the amount of material needed to make the box is:
[tex]\[ \boxed{41.5 \, \text{ft}^2} \][/tex]

So, the correct answer is:
A. [tex]$41.5 ft^2$[/tex]