Step 1:
The first step to converting 15998.424424318 to a fraction is to re-write 15998.424424318 in the form p/q where p and q are both positive integers. To start with, 15998.424424318 can be written as simply 15998.424424318/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 15998.424424318, which in this case is 9. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 15998.424424318/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 15998.424424318/1 each by 1000000000:
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 15998.424424318 as a fraction:
111989/7 / 1