Step 1:
The first step to converting 509791.01980816 to a fraction is to re-write 509791.01980816 in the form p/q where p and q are both positive integers. To start with, 509791.01980816 can be written as simply 509791.01980816/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 509791.01980816, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 509791.01980816/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 509791.01980816/1 each by 100000000:
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 509791.01980816 as a fraction:
509791/1 / 1