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Chapter 7: Probability
Definition: Event
An event is a subset of the sample space.
Note:
Each outcome in a sample space is an event. These events are called
simple events.
In the next section, we will introduce an approach to measure probability.
This approach is usually called the
classical approach
to probability.
Section Review
7-4 Classical Probability
If we can assume that all the simple events in a sample space have the same
chance of occurring, then we can measure the probability of an event as a
proportion, relative to the number of points in the sample space. Such a
probability measure is referred to as the
classical probability
for that event.
Definition: Classical Probability of an Event
If the outcomes in a sample space are equally likely to occur, then the
classical probability of an event A is defined to be
( )
Example 7-4:
If a two-child family is selected at random, what is the
probability of one boy?
e-Self Review