Step 1:
The first step to converting 86310.12080129 to a fraction is to re-write 86310.12080129 in the form p/q where p and q are both positive integers. To start with, 86310.12080129 can be written as simply 86310.12080129/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 86310.12080129, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 86310.12080129/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 86310.12080129/1 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 86310.12080129 as a fraction:
690481/8 / 1