Step 1:
The first step to converting 21454.535796547 to a fraction is to re-write 21454.535796547 in the form p/q where p and q are both positive integers. To start with, 21454.535796547 can be written as simply 21454.535796547/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 21454.535796547, which in this case is 9. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 21454.535796547/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 21454.535796547/1 each by 1000000000:
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 21454.535796547 as a fraction:
278909/13 / 1