Step 1:
The first step to converting 40290.72129 to a fraction is to re-write 40290.72129 in the form p/q where p and q are both positive integers. To start with, 40290.72129 can be written as simply 40290.72129/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 40290.72129, which in this case is 5. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 40290.72129/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 40290.72129/1 each by 100000:
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 40290.72129 as a fraction:
161163/4 / 1