Step 1:
The first step to converting 581.12687818221 to a fraction is to re-write 581.12687818221 in the form p/q where p and q are both positive integers. To start with, 581.12687818221 can be written as simply 581.12687818221/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 581.12687818221, which in this case is 11. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 581.12687818221/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 581.12687818221/1 each by 100000000000:
Step 3:
Now the last step is to simplify the fraction (if possible) by finding similar factors and cancelling them out, which leads to the following answer for 581.12687818221 as a fraction:
36611/63 / 1