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Problem 24 (2005 AMC 8)

AMC 8Normal

From module Arithmetic and Number Theory Basics

Problem

A certain calculator has only two keys [+1][+1] and [×2][\times2]. When you press one of the keys, the calculator automatically displays the result. For instance, if the calculator originally displayed "99" and you pressed [+1][+1] it would display "1010." If you then pressed [×2][\times2] it would display "2020." Starting with the display "11," what is the fewest number of keystrokes you would need to reach "200200"?

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