Problem Solving

试题详情

题目:

In the figure shown, if the area of the shaded region is 3 times the area of the smaller circular region, then the circumference of the larger circle is how many times the circumference of the smaller circle?

选项:

A、4
B、3
C、2
D、
E、

答案:

C

提问:

我是这么做的: pi R^2 / pi r^2 得到 R等于 r 乘以 根号三, 带入 2piR/ 2pir , 之后剩下根号三,请问老师,这个思路哪里不对?
评分: 0
浏览: 669
点我领取
免费专项课程
在线咨询