Fraction: As simple as it gets, turn a decimal number
into a fraction. Displayed are the original number, its
fraction and the decimal number of the fraction chosen,
as shown 0.876 => 106/121 => 0.876033. The fraction
must be in its simplest form so 876/1000 is not acceptable.
The accuracy is done to a set number of decimal points,
here set as 3 so to 3dp the two decimals in the example agree.

Try pi 3.14159265358979323846264338327950288419...
at various dps. How about e 2.718281828459045235...