Bluebook SAT Test Probability and Conditional Probability 1

Question 1

A bag contains 5 red marbles, 3 blue marbles, and 2 green marbles. If one marble is drawn at random, what is the probability that it is NOT green?

Accepted Answer

4/5

Answer

1/5

Answer

2/5

Answer

3/5

Question 2

A survey of 200 students found that 120 play sports and 80 play an instrument. If 40 students do both, how many students do neither?

Accepted Answer

40

Answer

80

Answer

120

Answer

160

Question 3

The two-way table shows pet ownership among 150 households.

Cat  No Cat
Dog       30     45
No Dog    25     50

Given that a household has a dog, what is the probability it also has a cat?

Accepted Answer

2/5

Answer

2/3

Answer

1/5

Answer

3/10

Question 4

A standard die is rolled twice. What is the probability of getting a 4 on the first roll and a number greater than 2 on the second roll?

Accepted Answer

1/9

Answer

1/6

Answer

2/9

Answer

1/3

Question 5

In a class of 30 students, 18 passed the math test and 12 passed the science test. If 6 students passed both, what is the probability that a randomly selected student passed at least one test?

Accepted Answer

4/5

Answer

3/5

Answer

2/3

Answer

1/2

Question 6

A jar has 4 red and 6 blue chips. Two chips are drawn without replacement. What is the probability that both chips are red?

Accepted Answer

2/15

Answer

4/25

Answer

8/25

Answer

1/5

Question 7

The table below shows 300 survey responses by age group and preference.

Prefer A  Prefer B
Under 30       90       60
30 and over    80       70

What is the probability that a randomly chosen respondent under 30 prefers A?

Accepted Answer

3/5

Answer

9/25

Answer

9/20

Answer

3/10