## Introductory Statistics 9th Edition

1. The probability of an event always lies in the range 0 to 1. 2. The sum of the probabilities of all simple events (or final outcomes) for an experiment, denoted by $∑P(E_{i})$, is always 1.
1. We can write the first property of probability as follows : $0\leq$∑P(E_{i})$\leq 1$ AND $0\leq$∑P(A_{i})$\leq 1$ An event that cannot occur has zero probability and is called an impossible event. An event that is certain to occur has a probability equal to 1 and is called a sure event. 2. We can write the first property of probability as follows : $∑P(E_{i}) =P(E_{1}) +P(E_{2}) +P(E_{3}) +...=1.0$