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# Rachel's Problem

Is it true that $ 99^n $ has $ 2n $ digits and $ 999^n $ has $ 3n $ digits? Investigate!

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Age 14 to 16

Challenge Level

- Problem
- Student Solutions

Is it true that $ 99^n $ has $ 2n $ digits and $ 999^n $ has $ 3n $ digits? Investigate!

(This problem was inspired by Rachel Galley's work on the problem called Giants in the June 1999 Six.)

If p is a positive integer and q is a negative integer, which of these expressions is the greatest?