In a figure, the radius of the inner circle of the tire is twice the width of the tire itself. To the nearest integer, what percent of the entire area is the area of the tire?

Question

My teacher told me the answer is 56%, by rounding the 55.5555...., but I don't understand how to do the problem!

***The figure is just a car tire, a circle inside a circle (thus, determining the inner radius and the width of the tire).

THANKS

Answer 1

If the tire has width w, then the inner radius is 2w, and the entire area has radius 3w.

So,

π(9w^2-4w^2)/π(9w^2) = 5/9 = .5555 or 56%

Answer 2

THANKS YOU SO MUCH!!!!!!!