A circle has radius 1 unit. What percent of its area lies outside of the circle with the same center and a radius of 1/2?

Respuesta :

Answer:

(3/4)pi

Step-by-step explanation:

Find the areas of the two circles and then subtract the smaller from the larger:

A of circle = (pi)r^2

Case 1:  r = 1 unit:  A = (pi)(1) = pi

Case 2:  r = 1/2 unit:  A = (pi)(1/2)^2 = pi/4

The area lying outside of the smaller circle is therefore (pi) - (pi)(1/4) = (3/4)pi