Step 1:
The first step to converting 643122.9410729 to a fraction is to re-write 643122.9410729 in the form p/q where p and q are both positive integers. To start with, 643122.9410729 can be written as simply 643122.9410729/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 643122.9410729, which in this case is 7. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 643122.9410729/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 643122.9410729/1 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 643122.9410729 as a fraction:
643123/1 / 1