13.1 ­ Experimental and Theoretical Probability.notebook
13.1: Experimental & Theoretical Probability
December 07, 2016
Date: 12/7
An outcome is the possible result of a situation or experiment.
An event may be a single outcome or a group of outcomes.
The set of all possible outcomes is the sample space
Ex:
Probability is a measure of the likelihood that an event will occur.
P(Event) = _________________________________________
You can write probability of an event as a fraction, decimal or percent
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13.1 ­ Experimental and Theoretical Probability.notebook
December 07, 2016
Two Types of Probability:
1. Experimental Probability – measures the likelihood of an event
based upon actual results of an experiment.
P(Event) = ___________________________________________
Ex 1). Of the students in Carlos’ homeroom, 11 are studying
Spanish, 6 are studying German, and 8 are studying French. If a
student is selected at random, what is the probability that he or she
is studying German?
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13.1 ­ Experimental and Theoretical Probability.notebook
December 07, 2016
Ex 2). A quality control inspector samples 750 LCD monitors and
finds defects in 4 of them.
a) What is the experimental probability that a monitor selected at
random will have a defect?
b) If the company manufactures 21,280 monitors in a month, how
many are likely to have a defect based on the quality control
inspector’s results?
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13.1 ­ Experimental and Theoretical Probability.notebook
December 07, 2016
2. Theoretical Probability – describes the likelihood of an event
based on mathematical reasoning.
Ex 3). Find the following probabilities when rolling a single die:
a) P(5)
b) P(even)
c) P(> 4)
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13.1 ­ Experimental and Theoretical Probability.notebook
December 07, 2016
Ex 4). Find the following probabilities when rolling two dice:
a) P(sum of 6)
b) P(sum even)
c) P(sum > 9)
d) P(sum < 1)
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13.1 ­ Experimental and Theoretical Probability.notebook
December 07, 2016
The complement of an event consists of all possible outcomes in the
sample space that are not part of the event.
Examples of Complements:
1. P(rolling a number less than 3)
2. P(choosing a consonant in the alphabet)
3. P(filling a head on a coin)
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13.1 ­ Experimental and Theoretical Probability.notebook
P(event) + P(not event) = _____
December 07, 2016
or P(not event) = ___________________
Ex 5). Use complements to find the probability that when a die is
rolled the number is not a 6.
Ex 6). There are 43 freshmen, 28 sophomores, 35 juniors, and 26 seniors
in the school auditorium. If a student is selected at random, what is the
probability that the student is not a junior?
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13.1 ­ Experimental and Theoretical Probability.notebook
December 07, 2016
Homework:
13.1 Worksheet
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