Step 1:
The first step to converting 1398218790.8913 to a fraction is to re-write 1398218790.8913 in the form p/q where p and q are both positive integers. To start with, 1398218790.8913 can be written as simply 1398218790.8913/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 1398218790.8913, which in this case is 4. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 1398218790.8913/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 1398218790.8913/1 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 1398218790.8913 as a fraction:
1398218790/1 / 1