Find the area of the wheel:
Area of a circle is found using the formula:
Area = PI x r^2
9 inch would be the diameter, so the radius would be 9/2 = 4.5 inches.
The area would be 3.14 x 4.5^2 = 63.6 square inches.
Now divide the price by the area to get price per square inch:
Cost per square inch = 18.60 / 63.6 = $0.29 (rounded to the nearest cent)
You need to multiply the two numbers. Or you can use long addition.
30 miles for a single gallon.
first we find out how many gallons would be used.
number of gallons = 1020/30
gallons = 34.
and since 1 gallon costs $4.06
34 gallons would cost = 34 x 4.06 = $138.04