Step 1:
The first step to converting 1216.6584428711 to a fraction is to re-write 1216.6584428711 in the form p/q where p and q are both positive integers. To start with, 1216.6584428711 can be written as simply 1216.6584428711/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 1216.6584428711, which in this case is 10. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 1216.6584428711/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 1216.6584428711/1 each by 10000000000:
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 1216.6584428711 as a fraction:
46233/38 / 1