Step 1:
The first step to converting 663320.39072401 to a fraction is to re-write 663320.39072401 in the form p/q where p and q are both positive integers. To start with, 663320.39072401 can be written as simply 663320.39072401/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 663320.39072401, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 663320.39072401/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 663320.39072401/1 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 663320.39072401 as a fraction:
663320/1 / 1