Probability

Question 1

P(A or B)

Answer 1

P(A) + P(B) = P(A and B)

Question 2

P(A and B)

Answer 2

P(A) * P(B)

Question 3

Independent Events

Answer 3

Events are independent events if the occurrence of one event does not affect the probability of the other

Question 4

Dependent Events

Answer 4

Events are dependent events if the occurrence of one event affects the probability of the other

Question 5

Probability of Dependent Events

Answer 5

(A and B) are dependent

Question 6

P(A and B)

Answer 6

P(A) * P(B/A)

Question 7

What is P(B/A)

Answer 7

The probability of B given that A has occurred

Question 8

When is a fraction dependent?

Answer 8

When both the denominators are different

Question 9

When is a fraction independent?

Answer 9

When both the denominators are the same

Question 10

What is a survey?

Answer 10

A survey is a study in which subjects are asked a question or a series of questions

Question 11

What is an experiment?

Answer 11

An experiment applies a treatment (a condition administered) to experimental units to observe an effect

Question 12

What is an observational study?

Answer 12

In an observational study a researcher observes and records measurements if variables of interest but does not impose a treatment

Question 13

What is an observational study?

Answer 13

In an observational study, a researcher observes and records measurements of variables of interest but does not impose a treatment

Question 14

P(A⋂B) - A and B

Answer 14

P(A) * P(B)

Question 15

P(A∪B) - A or B

Answer 15

Independent - P(A) + P(B)
Dependent - P(A) + P(B) - P(A⋂B)

Question 16

P(A^c)

Answer 16

1 - P(A)

Question 17

P(A/B) - Probability of A given B

Answer 17

P(A/B) = P(A⋂B)/P(B)

Question 18

Ex.
Set A: 1,2,2,3,5,7
Set B: 2,5,7

Answer 18

P(A∪B) - A or B = 1,3,2,5,7 (includes all)
P(A⋂B) - A and B = 2,5,7
(includes what #’s both have)