Step 1:
The first step to converting 128159.9998578 to a fraction is to re-write 128159.9998578 in the form p/q where p and q are both positive integers. To start with, 128159.9998578 can be written as simply 128159.9998578/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 128159.9998578, which in this case is 7. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 128159.9998578/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 128159.9998578/1 each by 10000000:
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 128159.9998578 as a fraction:
128160/1 / 1