The following elementary approach appears to be mechanically simpler than the approach found in the series chapter of some calculus texts.
Set = , so = 45.454545⋯.
Then, and so that the given repeating decimal is .
The charm of this approach is that a simple algorithm can be extracted, namely, divide the repeating digits by , where is the number of digits that are repeated.
Calculus texts, looking for an application of the geometric series, approach the problem as follows.
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As in the simpler method, the final result is .
Of course, the series advocate will claim that the given repeating decimal can immediately be represented as
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