Surface Area
The image shows the shape of a rectangular prism
The surface area of the shape is the sum of all the individual rectangles
There are 6 small rectangles. We'll find their area and add them up to find the total surface area.
The area of a rectangle of dimension L and W is:
A=L.W
First rectangle: 3 in x 7.5 in
A1 = 3 * 7.5 = 22.5 square inch
Second rectangle: 11.5 in x 3 in
A2 = 3 * 11.5 = 34.5 square inch
Note this rectangle is repeated twice
The third rectangle has the same area of the first rectangle:
A3 = 3 * 7.5 = 22.5 square inch
The fourth rectangle has dimensions of 7.5 x 11.5
A4 = 7.5 * 11.5 = 86.25 square inch
This rectangle is also repeated twice
The total area is :
A = A1 + A2 + A2 + A3 + A4 + A4
A = 22.5 + 34.5 + 34.5 + 22.5 + 86.25 + 86.25
A = 286.5 square inch
Answer: D.
