HMMT 二月 2000 · GEN 赛 · 第 20 题
HMMT February 2000 — GEN Round — Problem 20
题目详情
英文原题
- 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?
A CB Æ
解析
英文解析
- The area of the big ir le is ( ) = . The area of the ir le with diameter AB is
2 4
, and the area of the ir le with diameter B C is . Th us, the p er en tage of the big 9
25 94
25 4 912
4 4
ir le that is shaded is = = = 48% .
25 2525 4