Step 1:
The first step to converting 39945.4578 to a fraction is to re-write 39945.4578 in the form p/q where p and q are both positive integers. To start with, 39945.4578 can be written as simply 39945.4578/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 39945.4578, which in this case is 4. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 39945.4578/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 39945.4578/1 each by 10000:
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 39945.4578 as a fraction:
439400/11 / 1