Answer:
The minimum width of the placemat is 10 inches.
Step-by-step explanation:
Let suppose that placemat has a square form, whose width must be at least equal to the diameter of the pizza, so that pizza does not touch the table. Hence, the following relationship is obtained:

Where:
- Width of the placemat, measured in inches.
- Diameter of pizza, measured in inches.
The area of the pizza, measured in square inches, is determined by this formula:

The diameter is cleared afterwards:

If
and
, then:


The minimum width of the placemat is 10 inches.
8.11 as an improper fraction is 811 over 100 811/100 if you convert
The solutions can be 0,1.5,1/2,1,0.03.
I think the correct answer is C. Since a=πr², in order to get the area to become 1/4 of what it was previously, the radius needs to be cut in half to make the divide that side by 4. a=π(r/2)²=πr²/4 and will therefore multiply the area by 1/4.