Step 1:
The first step to converting 406436.80639828 to a fraction is to re-write 406436.80639828 in the form p/q where p and q are both positive integers. To start with, 406436.80639828 can be written as simply 406436.80639828/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 406436.80639828, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 406436.80639828/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 406436.80639828/1 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 406436.80639828 as a fraction:
406437/1 / 1