Step 1:
The first step to converting 399765.8405013 to a fraction is to re-write 399765.8405013 in the form p/q where p and q are both positive integers. To start with, 399765.8405013 can be written as simply 399765.8405013/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 399765.8405013, which in this case is 7. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 399765.8405013/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 399765.8405013/1 each by 10000000:
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 399765.8405013 as a fraction:
399766/1 / 1