¶ 2010 AMC8 Problem 19
Problem:
The two circles pictured have the same center . Chord is tangent to the inner circle at is , and chord has length . What is the area between the two circles?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
In the right triangle is . By the Pythagorean Theorem, so . The area of the outer circle is and the area of the inner circle is . The area between the circles is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions