Step 1:
The first step to converting 639900.4501041 to a fraction is to re-write 639900.4501041 in the form p/q where p and q are both positive integers. To start with, 639900.4501041 can be written as simply 639900.4501041/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 639900.4501041, which in this case is 7. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 639900.4501041/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 639900.4501041/1 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 639900.4501041 as a fraction:
639900/1 / 1