Step 1:
The first step to converting 409456961.4218 to a fraction is to re-write 409456961.4218 in the form p/q where p and q are both positive integers. To start with, 409456961.4218 can be written as simply 409456961.4218/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 409456961.4218, which in this case is 4. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 409456961.4218/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 409456961.4218/1 each by 10000:
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 409456961.4218 as a fraction:
409456961/1 / 1