1. Sample Spaces
COURSE 2 LESSON 12-4
a. Make a table to show the sample space for tossing two coins. Write the outcomes as ordered pairs.
There are 4 possible outcomes.
H T H T
( , )
b. Find P(T, T), the probability of tossing two tails.
There is one outcome for tossing two tails. There are four possible outcomes. So the probability of tossing two tails is . 1 4
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2. Sample Spaces
COURSE 2 LESSON 12-4
Suppose you can go west or northwest by train, bus, or car.
a. Draw a tree diagram to show the sample space.
There are 6 possible outcomes.
Direction
West
Northwest
Outcomes
Train, West
Train, Northwest
Bus, West
Bus, Northwest
Car, West
Car, Northwest
Vehicle
Train
Bus
Car
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3. Sample Spaces (continued)
COURSE 2 LESSON 12-4
(continued)
b.  What is the probability of a random selection that results in a bus trip west?
Direction
West
Northwest
Outcomes
Train, West
Train, Northwest
Bus, West
Bus, Northwest
Car, West
Car, Northwest
Vehicle
Train
Bus
Car
There is one favorable outcome (bus, west) out of six possible outcomes. The probability is . 1 6
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4. Sample Spaces
COURSE 2 LESSON 12-4
How many kinds of coin purses are available if the purses come in small or large sizes and colors red, blue, yellow, and black?
Sizes Colors
small red
large blue
yellow
black
Use the counting principle.
Size Color
number of choices  number of choices
2  4 = 8
There are 8 different kinds of coin purses available.
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5. Sample Spaces
COURSE 2 LESSON 12-4
You pick a card at random from cards labeled 1, 2, or 3 and then spin a spinner divided into thirds, each of which is labeled with numbers 1, 2, or 3.
1. Make a table showing the sample space.
1 2 3
1 (1, 1) (2, 1) (3, 1)
2 (1, 2) (2, 2) (3, 2)
3 (1, 3) (2, 3) (3, 3)
2. How many possible outcomes are there? 9
3. What is the probability of two 3s? 1 9
4. What is the probability of picking a card and spinning the same number? 1 3
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