7th Grade Math

436 Probability and Predictions

a. PETS The animal shelter has both male and female Labradors in

yellow, brown, or black. Find the sample space for all possible

Labradors available at the shelter.

Find Probability

GAMES Refer to the Explore at the start of this lesson. Find the

sample space. Then find the probability that player 2 wins.

Make a tree diagram to show the sample space.

(

(

3

(

3

((

(3

((

(3

(

#BH
"

4BNQMF

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# 4QBDF

There are 4 equally likely outcomes with 2 favoring each player.

So, the probability that player 2 wins is _^24 , or _^12 , or 0.5, or 50%.

b. GAMES Delmar tosses three coins. If all three coins show up heads,

Delmar wins. Otherwise, Kara wins. Find the sample space. Then

find the probability that Delmar wins.

Fair Game Fair Game A fair game is

one in which each player

has an equal chance of

winning. This game is a

fair game.

Example 1 For each situation, find the sample space using a tree diagram.

(^11) A coin is tossed twice.

2. A pair of brown or black sandals are available in sizes 7, 8, or 9.


3. FOOD The table shows the sandwich choices for
   the school picnic. Find the sample space for a

Meat Bread

ham

turkey

rye

sourdough

white

sandwich consisting of one type of meat and one

type of bread.

Example 2 4. GAMES Gerardo spins a spinner with four sections of equal size, labeled

A, B, C, and D, twice. If letter A is spun at least once, Gerardo wins.

Otherwise, Odell wins. Find the sample space. Then find the probability

that Odell wins.

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