ABSTRACT
Equation 2.2 will not make a mathematician happy, but it is extensively used in practice because it is in accord with the idea behind Equation 2.1 and gives useful results.
As an illustration of the use of Equation 2.2, consider the experiment of tossing a coin 100 times and recording how many times the result is “heads” and how many times it is “tails.” Assume that the result is
Heads: 48 times Tails: 52 times
On the basis of Equation 2.2, the probability of getting heads or tails if the coin is tossed once more is
P
P
( ) .
