1. Chapter IV Statistic and simple probability

2. A. Meaning of probability 1.Random event 2.Simple event 3.Relative frequent and probability of an event Relative frequent(fr) the appearing of K notated as. 4.Point and space sample in theory of probability. There are three ways to determine space of sample from sample points, they are listing, table, and hierarchical diagram.

3. B. Calculating probability 1.Definition of probability 2.Calculating probability of an event by relative frequency Relative frequency and probability of an event Relative frequency notated by the following formula. 3.Calculation of probability of an event by relative frequency If each sample point of member of space sample S has same probability, therefore probability of an event K which has members n(K) notated as

4. 4.Value of probability If the value of probability of a event is zero, it means the event is impossible, for example probability of the sun rises in the west. If probability of an event is 1, it menas the event is must be happen, for example probability of human will die. C. Expected probability Expected probability of an event is an expectation of how many the observed event appeared in several trials. With P(K) = probability of an event K N = Number of trials.