AMC 8 2005 Problem 24
AMC8 2005 年第 24 题
基本计数原理★★★★☆
A certain calculator has only two keys [+1] and [x2]. When you press one of the keys, the calculator automatically displays the result. For instance, if the calculator originally displayed "9" and you pressed [+1], it would display "10." If you then pressed [x2], it would display "20." Starting with the display "1," what is the fewest number of keystrokes you would need to reach "200"?
某个计算器只有两个键［＋1］和［x2］。按其中一个键时，计算器会自动显示计算结果，例如， 如果计算器最初显示"9"，当你按下［＋1］，它将显示"10"。如果你接着再按下［x2］，它将显示"20"。从显示"1"开始，你最少需要按键多少次才能得到结果"200"？
- A.8
- B.9
- C.10
- D.11
- E.12
正确答案 · Correct Answer
B
解析 · Solution
解析整理中
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