a poster reproduces the Mona Lisa in the original size, but adds a 4 1/2 inch border around each side. What is the perimeter of this poster if the length is 30 3/10" and width is 20 7/8"?

Answer 1

Not clear if the dimensions given shows the poster before or after the border is added.

anyway, 9 inches were added both the length and the width, so you take it from there.
Might be a good idea to make a sketch to see why you would add 4.5 twice.

Answer 2

the dims are of the poster and then he adds 4 1/2 inch

Answer 3

So, follow the instructions that I gave you, let me know what you got.

Answer 4

we got 119 3/20 for the perimeter

Answer 5

old width = 20.875
new width = 20.875 + 9 = 29.875

old length = 30.3
new length = 30.3+9 = 39.3

new perimeter
= 2(width + length)
= 2(30.3+39.3) = 138.35

in fraction form that would be 138 7/20

I have no idea how you could have come up with your answer if you followed my instructions.

Answer 6

last calculations should say:

new perimeter
= 2(width + length)
= 2(29.875+39.3) = 138.35

in fraction form that would be 138 7/20