Step 1:
The first step to converting 394.2121451367 to a fraction is to re-write 394.2121451367 in the form p/q where p and q are both positive integers. To start with, 394.2121451367 can be written as simply 394.2121451367/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 394.2121451367, which in this case is 10. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 394.2121451367/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 394.2121451367/1 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 394.2121451367 as a fraction:
13009/33 / 1