选择题
2020 AMC 8 Problem 24: Tile Ratio
A large square region is paved with n² gray square tiles, each measuring s inches on a side. A border d inches wide surrounds each tile. The figure below shows the case for n = 3. When n = 24, the 576 gray tiles cover 64% of the area of the large square region. What is the ratio d/s for this larger value of n?
2020 AMC 8 第 24 题：平铺比例
一个大的方形区域铺有 n² 块灰色方形瓷砖，每块边长为 s 英寸。每块瓷砖周围都有 d 英寸宽的边框。下图显示了 n = 3 的情况。当 n = 24 时，576 个灰色瓷砖覆盖了大正方形区域面积的 64%。对于较大的 n 值，d/s 的比率是多少
A.
6/25
B.
1/4
C.
9/25
D.
7/16
E.
9/16