PRACTICE: Independent & dependent probability
PRACTICE: Independent & dependent probability A dark bag contains 4 red marbles, 8 blue marbles, 3 green marbles, and 5 yellow marbles. Find the probability of drawing out marbles as indicated in each of the given situations. Express your answer as a fraction in lowest terms. EXAMPLE 1: independent case
EXAMPLE 2: dependent case
What’s the probability of choosing a blue marble, returning it, and then choosing a blue marble?
What’s the probability of choosing a blue marble, NOT returning it, and then choosing a blue marble?
8 20
8 20
2
2
4
8
5
5
25
20
= =
7 19
2
7
5
19
=
=
14 95
YOUR TURN: 1) What’s the probability of choosing a red marble, returning it, and then choosing a yellow marble?
2) What’s the probability of choosing a green marble, NOT returning it, and then choosing a green marble?
3) What’s the probability of choosing a yellow marble, NOT returning it, and then choosing a red marble?
4) What’s the probability of choosing a blue marble, returning it, and then choosing a yellow marble?
5) What’s the probability of choosing a green marble, NOT returning it, and then choosing a blue marble?
6) What’s the probability of choosing a blue marble, returning it, and then choosing a green marble?
7) What’s the probability of choosing a red marble, returning it, and then choosing a green marble?
8) What’s the probability of choosing a yellow marble, NOT returning it, and then choosing a blue marble?
20 1
2)
190 3
3)
19 1
4)
10 1
5)
95 6
11/23/2017
Answers: 1)
6)
50 3
7)
100 3
© D. Stark 2017
PRACTICE: Independent & dependent probability
8)
19 2
EXAMPLE 2: dependent case
What’s the probability of choosing a blue marble, returning it, and then choosing a blue marble?
What’s the probability of choosing a blue marble, NOT returning it, and then choosing a blue marble?
8 20
8 20
2
2
4
8
5
5
25
20
= =
7 19
2
7
5
19
=
=
14 95
YOUR TURN: 1) What’s the probability of choosing a red marble, returning it, and then choosing a yellow marble?
2) What’s the probability of choosing a green marble, NOT returning it, and then choosing a green marble?
3) What’s the probability of choosing a yellow marble, NOT returning it, and then choosing a red marble?
4) What’s the probability of choosing a blue marble, returning it, and then choosing a yellow marble?
5) What’s the probability of choosing a green marble, NOT returning it, and then choosing a blue marble?
6) What’s the probability of choosing a blue marble, returning it, and then choosing a green marble?
7) What’s the probability of choosing a red marble, returning it, and then choosing a green marble?
8) What’s the probability of choosing a yellow marble, NOT returning it, and then choosing a blue marble?
20 1
2)
190 3
3)
19 1
4)
10 1
5)
95 6
11/23/2017
Answers: 1)
6)
50 3
7)
100 3
© D. Stark 2017
PRACTICE: Independent & dependent probability
8)
19 2
