Hello! The answer to your question would be as followed:
First we need to find the area of the wheel:
We can use the formula of a circle
Area = PI * r^2
The diameter is nine inches, so the radius would be 9/2 = 4.5 inches
The area would be found by this equation:
3.14 x 4.5^2 = 63.6 square inches.
Then, we now divide the price by the area to get the price per square inch:
The cost per square inch = 18.60 / 63.6 = $0.29
Rounded to the nearest cent