Step 1:
The first step to converting 20599.403864558 to a fraction is to re-write 20599.403864558 in the form p/q where p and q are both positive integers. To start with, 20599.403864558 can be written as simply 20599.403864558/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 20599.403864558, which in this case is 9. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 20599.403864558/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 20599.403864558/1 each by 1000000000:
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 20599.403864558 as a fraction:
102997/5 / 1