Blanca is going to use a box that is a rectangular prism for a card box at her son’s birthday party. She will wrap and decorate the box. The dimensions of the box are shown in the diagram.

10.5 , 7in, 9.1 in

What is the total surface area of the box in square inches?

1 answer

To find the total surface area of the rectangular prism, we need to find the area of each face and sum them up.

The rectangular prism has 6 faces: 2 rectangular faces on the top and bottom, and 4 rectangular faces on the sides.

The area of each rectangular face is found by multiplying its length and width.

For the top and bottom faces:
Area of the top face = Length * Width
= 10.5 in * 9.1 in
= 95.55 in² (rounded to two decimal places)

Since the top and bottom faces are identical, their total area is twice the area of one of the faces = 2 * 95.55 in² = 191.10 in² (rounded to two decimal places)

For the side faces:
Area of each side face = Length * Width
= 10.5 in * 7 in
= 73.5 in²

Since there are 4 side faces, their total area is 4 * 73.5 in² = 294 in²

The total surface area of the box is the sum of the areas of all its faces:
Total surface area = Area of top and bottom faces + Area of side faces
= 191.10 in² + 294 in²
= 485.10 in² (rounded to two decimal places)

Therefore, the total surface area of the box is 485.10 square inches.