Step 1:
The first step to converting 3557.398 to a fraction is to re-write 3557.398 in the form p/q where p and q are both positive integers. To start with, 3557.398 can be written as simply 3557.398/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 3557.398, which in this case is 3. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 3557.398/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 3557.398/1 each by 1000:
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 3557.398 as a fraction:
17787/5 / 1