Step 1:
The first step to converting 19858346221.642 to a fraction is to re-write 19858346221.642 in the form p/q where p and q are both positive integers. To start with, 19858346221.642 can be written as simply 19858346221.642/1 to technically be written as a fraction.
Step 2:
Next, we will count the number of fractional digits after the decimal point in 19858346221.642, which in this case is 3. For however many digits after the decimal point there are, we will multiply the numerator and denominator of 19858346221.642/1 each by 10 to the power of that many digits. So, in this case, we will multiply the numerator and denominator of 19858346221.642/1 each by 1000:
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 19858346221.642 as a fraction:
19858346221/1 / 1