Download 2CH10L1 - Kyrene School District

10-1 Probability
Warm Up
Problem of the Day
Lesson Presentation
Course 2
10-1 Probability
Warm Up
Write each fraction in simplest form.
1. 15
21
2. 48
64
3. 9
81
4. 30
45
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5
7
3
4
1
9
2
3
10-1 Probability
Problem of the Day
You roll a regular pair of number cubes.
How likely is it that the product of the
two numbers is odd and greater than
25? Explain.
Impossible; the only possible products
greater than 25 (30 and 36) are even.
Course 2
10-1 Probability
Learn to use informal measures of
probability.
Course 2
10-1 Probability
Insert Lesson Title Here
Vocabulary
experiment
outcome
event
probability
equally likely
impossible
certain
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10-1 Probability
Suppose you rolled one of these dice. The blue
one is equally likely to land on any of the six
numbers. The red one is more likely to land on
one of the larger faces. So the likelihood is
greater that you would roll a 5 with the red die
than with the blue one.
Course 2
10-1 Probability
Any activity involving chance, such as the roll of
a die, is an experiment. The result of an
experiment is an outcome. An event is a set of
one or more outcomes.
Events that have the same probability are equally
likely. Probability is the measure of how likely an
event is to occur. The more likely an event is to
occur, the higher its probability. The less likely an
event is to occur, the lower its probability.
Course 2
10-1 Probability
Additional Example 1A: Determining the Likelihood
of an Event
A bag contains circular chips that are the
same size and weight. There are 8 purple
chips, 4 pink chips, 8 white chips, and 2 blue
chips in the bag.
A. Would you be more likely to pull a purple
chip or a blue chip from the bag?
Since there are more purple chips than blue
chips in the bag, it is more likely you would
pull a purple chip than a blue chip from the
bag.
Course 2
10-1 Probability
Additional Example 1B: Determining the Likelihood
of an Event
A bag contains circular chips that are the
same size and weight. There are 8 purple
chips, 4 pink chips, 8 white chips, and 2 blue
chips in the bag.
B. Would you be more likely to pull a white
chip or a purple chip from the bag?
Since the number of white chips equals the
number of purple chips in the bag, it is just as
likely that you would pull a white chip as a
purple from the bag. The events are equally
likely.
Course 2
10-1 Insert
Lesson Title Here
Probability
Try This: Example 1A
A bag contains 16 marbles that are similar in
weight and size. There are 8 blue marbles, 4
red marbles, 2 white marbles, and 2 yellow
marbles in the bag.
A. Would you be more likely to pull a white
or a yellow marble from the bag?
Since there are an equal number of white
marbles and yellow marbles, it is just as likely
that you would pull a white marble as a yellow
marble. The events are equally likely.
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10-1 Insert
Lesson Title Here
Probability
Try This: Example 1B
A bag contains 16 marbles that are similar in
weight and size. There are 8 blue marbles, 4
red marbles, 2 white marbles, and 2 yellow
marbles in the bag.
B. Would you be more likely to pull out a
yellow marble or a red marble?
Since there are more red marbles than yellow
marbles, it is more likely that you would pull a
red marble than a yellow marble.
Course 2
10-1 Probability
Every event is either impossible, certain, or somewhere
between these extremes. An event is mathematically
impossible if it can never happen and mathematically
certain if it will always happen. If an event is as likely
as not, the probability that it will happen is the same
as the probability that it will not happen.
Impossible
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Unlikely
As likely
as not
Likely
Certain
10-1 Probability
Additional Example 2A: Classifying Likelihood
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
A. Tina has a soccer game on Saturday.
How likely is it that she is at home all
day on Saturday?
Tina could have gotten sick on Saturday
morning and stayed home. However, it is
unlikely that she is at home on Saturday.
Course 2
10-1 Probability
Additional Example 2B: Classifying Likelihood
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
B. Jason is canoeing on the river. How likely
is it that he is shopping with Kevin?
It is impossible that Jason is shopping with
Kevin.
Course 2
10-1 Probability
Additional Example 2C: Classifying Likelihood
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
C. Maureen is running with her mother.
Her mother is in the park. How likely
is it that Maureen is at the park?
It is certain that Maureen is running at the park.
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10-1 Probability
Additional Example 2D: Classifying Likelihood
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
D. There are 12 black and 12 red checkers in
a box. How likely is it that you will
randomly draw a red checker?
Since the number of black checkers equals
the number of red checkers, it is as likely as
not that you will draw a red checker.
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Lesson Title Here
Probability
Try This: Example 2A
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
A. The math class has a test each Friday.
Today is Friday. How likely is it that the
math class will be having a test today?
It is certain that the math class will have a
test today.
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Lesson Title Here
Probability
Try This: Example 2B
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
B. Gerald has never played two tennis
matches in one day. He already played one
match today. How likely is it that he will
play another match?
Since Gerald has never played two tennis
matches in one day, it is unlikely that he
will play another match today.
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10-1 Insert
Lesson Title Here
Probability
Try This: Example 2C
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
C. Maggie has a doctor’s appointment
Monday morning. How likely is it she will
miss some classes Monday morning?
It is likely that Maggie will miss some
classes Monday morning.
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Lesson Title Here
Probability
Try This: Example 2D
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
D. There are five 2’s and five 3’s in a set of
10 cards. If you draw a card, how likely is
it that you will randomly draw a 3?
Since the number of 2’s equals the number
of 3’s, it is as likely as not that you will draw
a 3.
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10-1 Probability
Additional Example 3: School Application
Mandy’s science teacher almost always
introduces a new chapter by conducting an
experiment. Mandy’s class finished a chapter
on Friday. Should Mandy expect the teacher to
conduct an experiment next week? Explain.
Since the class just finished a chapter, they will
be starting a new chapter. It is likely the teacher
will conduct an experiment.
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10-1 Insert
Lesson Title Here
Probability
Try This: Example 3
After completing a unit chapter, Alice’s
keyboarding class usually begins the next
class day with a time trial exercise, practicing
the previously learned skills. It is Wednesday
and a unit chapter was completed the
previous day. Will the class start with a time
trial exercise?
If the teacher keeps to her planned schedule, it is
likely the class will start with a time trial.
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10-1 Probability
Insert Lesson Title Here
Lesson Quiz: Part 1
A bag holds 4 red marbles, 3 green marbles,
3 yellow marbles, and 2 blue marbles. You
pull one out without looking.
1. Is it more likely to be red or blue?
red
2. Is it more likely to be green or yellow?
equally likely
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10-1 Probability
Insert Lesson Title Here
Lesson Quiz: Part 2
Determine whether each event is impossible,
unlikely, as likely as not, likely, or certain.
3. Bonnie’s Spanish club meets on Tuesday
afternoons. How likely is it that Bonnie is at the
mall on Tuesday afternoon?
unlikely
4. There are 12 SUVs and 12 vans in a parking lot.
How likely is it that the next vehicle to move is a
van?
as likely as not
Course 2