Unit 4 – Combinatorics and ProbabilitySection 4.4 – Probability with Combinations

Calculator Required

16

3

A bag contains seven pennies, four nickels, and five dimes. Three coins are selected at random.

Find the probability of each event.

e. One penny, one dime, one nickel7 4 5

1 1 1

f. One dime, two nickels

16

3

7 4 5

0 2 1

A bag contains five red, nine blue and six white marbles. Twoare selected at random. Find the probability of each selection.

a. two red

20

2

5 9 6

2 0 0

b. two blue

20

2

5 9 6

0 2 0

c. one red, one blue

20

2

5 9 6

1 1 0

b. one red, one white

20

2

5 9 6

1 0 1

Sharon has eight mystery books and nine science fiction books.Four are selected at random. Find the probability of:

a. four mystery books

17

4

8 9

4 0

b. four sci-fi books

17

4

8 9

0 4

c. two mysteries, two sci-fi

17

4

8 9

2 2

d. Three mysteries, one sci-fi

17

4

8 9

3 1

A ball contains three red balls, two blue balls, and one whiteball. If two are drawn, find the probability that both are red.

6

2

3 3

2 0

Two die are rolled. Find the probability that their sum is 9.

6 6

1 2 3 4 5 6X X

4 1

A card is drawn from a 52 card bridge deck. A second card is then drawn. Find the probability of each event.

a. both are tens 4

2 152 221

2

b. both are aces 4

2 152 221

2

c. either both are tens or both are aces. 4 4

2 2 252 52 221

2 2