posted by kelly .
Myra's bulletin board has a width of 60 inches. When she originally decorated it she needed 192 inches of border material. How many inches high is the bulletin board?
Again, you are going to be using the perimeter formula. The question tells you that the border is 192 inches which means that the total perimeter of this bulletin board is 192 inches. Since it is a bulletin board, I am going to assume that the shape is a rectangle. What do we know about rectangles? We know the the widths are the same and lengths are the same. We know that the width of one side is 60 inches therefore the width of the other side is 60 inches as well. Let's plug what we already know into our equation:
Perimeter = Length + Width + Length + Width
192 = Length + 60 + Length + 60
192 = Length + Length + 120
192 - 120 = Length + Length
72 = Length + Length
72 = 2 * Length
72/2 = Length
36 = Length
Therefore, the height of the bulletin board is 36 inches.