Step 1:
The first step to converting 665887.54268921 to a fraction is to re-write 665887.54268921 in the form p/q where p and q are both positive integers. To start with, 665887.54268921 can be written as simply 665887.54268921/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 665887.54268921, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 665887.54268921/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 665887.54268921/1 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 665887.54268921 as a fraction:
665887/1 / 1