Step 1:
The first step to converting 128915.99939469 to a fraction is to re-write 128915.99939469 in the form p/q where p and q are both positive integers. To start with, 128915.99939469 can be written as simply 128915.99939469/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 128915.99939469, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 128915.99939469/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 128915.99939469/1 each by 100000000:
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 128915.99939469 as a fraction:
128916/1 / 1