Answer:
124/999
Step-by-step explanation:
A recurring decimal fraction can be expressed as a rational number by using the recurring digits in the numerator and an equal number of 9s in the denominator:
[tex]0.\overline{124}=\dfrac{124}{999}[/tex]
This fraction cannot be reduced.
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Additional comment
If the recurring digits don't start at the decimal point, then you can determine the fraction by ...
In this case, you would get ...
[tex]1000x = 124.\overline{124}\\\\1000x-x=124.\overline{124}-0.\overline{124}=124\\\\x=\dfrac{124}{999}[/tex]