[tex]3^{20}\equiv 1\pmod{100}[/tex](adsbygoogle = window.adsbygoogle || []).push({});

How can I show this? I can't see any use of Fermat's Little Theorem here (unless I'm just missing it).

FLT is the only way I know how to do these. Does anyone have a suggestion on how to do it for something like this?

Thanks.

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# Homework Help: Number Theory

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