AMC 10 Step by Step
2023 AMC 10AProblem 15P11-15~4 minPrint

An even number of circles are nested, starting with a radius of 11 and increasing by 11 each time, all sharing a common point. The region between every other circle is shaded, starting with the region inside the circle of radius 22 but outside the circle of radius 1.1. An example showing 88 circles is displayed below. What is the least number of circles needed to make the total shaded area at least 2023π2023\pi ?

figure

Log in to save your progress.

Similar problems

Problem © Mathematical Association of America (MAA), American Mathematics Competitions. Reproduced for non-commercial educational use. Solution and commentary are original to this site.