11.5 Multiplication or Division to Recorded Count
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Summary
Radioactive decay being a random process, it is important to represent results
along with the standard deviation. Though it is desirable to count large number of digits within one observation to get an accurate value of the standard
deviation, one may have to make a compromise while dealing with short-lived
isotopes with low activity, as well as with long-lived isotopes of low activity.
In both cases, square root of single observation may be taken as approximately
equal to the standard deviation. It is also obvious from these discussions that
mere representation of mean is not the best way to represent the data. When
digits recorded are to be multiplied, divided subtracted or added to another
either fixed or variable number, the standard deviation of the final result can
also be expressed by applying the appropriate equations as discussed in this
chapter.