Step 1:
The first step to converting 900.4220670801 to a fraction is to re-write 900.4220670801 in the form p/q where p and q are both positive integers. To start with, 900.4220670801 can be written as simply 900.4220670801/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 900.4220670801, which in this case is 10. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 900.4220670801/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 900.4220670801/1 each by 10000000000:
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 900.4220670801 as a fraction:
40519/45 / 1