AMC 8 2020 Problem 21
AMC8 2020 年第 21 题
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A game board consists of 64 squares that alternate in color between black and white. The figure below shows square P in the bottom row and square Q in the top row. A marker is placed at P. A step consists of moving the marker onto one of the adjoining white squares in the row above. How many 7 -step paths are there from P to Q? (The figure shows a sample path.)
一种游戏板由 64 个黑白相间的方块组成。下图显示了底行中的一个正方形 P 和顶行中的一个正方形 Q。在正方形 P 上放了一个标记,将标记移到上面一行中相邻的一个白色正方形上,这个操作称为一步。从 P 到 Q 有多少种 7 步路径?(图中显示了一种可能的示例路径)。

- A.28
- B.30
- C.32
- D.33
- E.35
正确答案 · Correct Answer
A
解析 · Solution
解析整理中
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