the formula for the perimeter of a rectangle is
P=2l*2w
plug in the data we know
27.5=2(9)+2w
27.5=18+2w
subtract 18 from both sides
9.5=2w
divide both sides by 2
4.25=w
The width of the box is 4.25feet
Now we can solve for the area. The formula for the area of a rectangle is
A=l*w
plug in the data we know
A=9*4.25
A=38.25ft²
Answer=38.25ft²