**Properties of Probability**

Let S be a sample space consisting of n distinct outcomes, s_{1} ,s_{2 },………s_{n}. An acceptable probability assignment consist of assigning to each outcome s_{i} a number p_{1} (the probability of s_{i}) according to these rules.

**a.** The probability of each outcome is a number between 0 and 1.

0 ≤ p_{1} ≤ 1, 0 ≤ p_{2}≤ 1 ,…….0 ≤ p_{n }≤ 1

**b.** The sum of the probabilities of all possible outcomes is 1.

p_{1} + p_{2} + p_{3} + ….. + p_{n }= 1