Step 1:
The first step to converting 436.63872499421 to a fraction is to re-write 436.63872499421 in the form p/q where p and q are both positive integers. To start with, 436.63872499421 can be written as simply 436.63872499421/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 436.63872499421, which in this case is 11. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 436.63872499421/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 436.63872499421/1 each by 100000000000:
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 436.63872499421 as a fraction:
15719/36 / 1