Function Repository Resource:

RepeatingDecimalToRational

Find a rational number equivalent to a real number with repeating digits

Contributed by: Wolfram|Alpha Math Team

ResourceFunction["RepeatingDecimalToRational"][x,n]

returns a rational number that approximates x, assuming the last n digits of x repeat infinitely.

ResourceFunction["RepeatingDecimalToRational"][x,{a,b,c,…}]

returns a rational number that approximates x with the repeating digits {a,b,c,…} appended.

Details and Options

ResourceFunction["RepeatingDecimalToRational"] expects a real number as its first argument.

Find a fractional representation for 0.333…:

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Out[1]=

Check the fractional representation of 1/7:

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Specify which digits are repeating:

In[3]:=

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Numericize that:

In[4]:=

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