How to represent a number with a repeating decimal as a ratio of integers [duplicate]

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How to express the following number as a ratio of integers:

$10.1\overline {35}$

where 35 repeats infinetly. so:

$10.135353535353535353535353535\cdots$

Basically I did this so far

$\frac {101}{10} + (.35) *$ geometric infinite series $\left(\frac 1{10}\right)^n$

But this isn't right. What am I doing wrong with my infinite series? I want to make it correct so I can use the sum formula.

The answer is: $\frac {5017}{495}$

But I'm not sure how to get that answer.

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1 Answer

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Let say $x=10.1353535...$.

Then $1000x=10135.3535...$ and $10x=101.3535...$

Subtracting these both equations gives

$990x=10034$ which after simplifying gives

$x=10.1353535..=5017/495$

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