0.21212121212121212121...=7/33.
How did I find this out?
n=0.212121212121...
100n=21.212121212121...
100n-n=99n=21
Therefore n=21/99=7/33
The repeating decimal 0. 21 can be expressed as the fraction 33 7 . This is done by setting the decimal equal to a variable, multiplying to align the repeating part, and then solving the resulting equation. After simplifying, we arrive at the final fraction in its simplest form.
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