HMMT 二月 2000 · GEN 赛 · 第 20 题
HMMT February 2000 — GEN Round — Problem 20
题目详情
- Giv en: AC has length 5, semi ir le AB has radius 1, semi ir le B C has diameter 3. What p er en t of the the big ir le is shaded? B A C Æ
解析
- The area of the big ir le is ( ) = . The area of the ir le with diameter AB is 2 4 9 , and the area of the ir le with diameter B C is . Th us, the p er en tage of the big 4 25 9 12 25 4 9 4 4 ir le that is shaded is = = = 48% . 25 25 25 4