c Kendra Kilmer October 11, 2011
Section 7.2  Definition of Probability
Definition:
Suppose we repeat an experiment
n
times and an event
E
occurs
m
of those times. Then
m
n
is called
the
relative frequency
of the event
E
.
Example 1:
Let’s say you flip a coin 100 times and a head occurs 61 times. What is the relative frequency of the
event
E
=
{
x

x
is heads
}
?
Definition:
Often, the more we repeat an experiment, the more the relative frequency approaches a certain value.
We call this the
empirical probability
of the event.
Definition:
The
probability
of an event is a number between 0 and 1 that represents the likelihood of the event
occuring. The larger the probability, the more likely the event is to occur.
Definition:
An event which consists of exactly one outcome is called a
simple event
of the experiment.
Example 2:
List the simple events associated with each of the given experiments:
a)
A nickel and a dime are tossed, and the result of heads or tails is recorded for each coin.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
This is the end of the preview.
Sign up
to
access the rest of the document.
 Fall '08
 JillZarestky
 Probability, Probability theory, Probability space

Click to edit the document details