Step 1:
The first step to converting 644764.72758476 to a fraction is to re-write 644764.72758476 in the form p/q where p and q are both positive integers. To start with, 644764.72758476 can be written as simply 644764.72758476/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 644764.72758476, which in this case is 8. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 644764.72758476/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 644764.72758476/1 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 644764.72758476 as a fraction:
644765/1 / 1