ch 5
Which of the following is a Subjective Probability?
If you apply for a job after graduation, your chance of getting the job is 83%.
Which of the following best describes the meaning of "outcome" in the context of a probability experiment?
One and only one result of the experiment.
Which of the following formulas correctly represents the general rule of multiplication for two events?
P(A and B) = P(A)P(B|A)
Which of the following expressions accurately represents the General Rule of Addition?
P(A or B) = P(A) + P(B) - P(A and B)
What does it mean when an experiment has a set of events that are collectively exhaustive?
That at least one of the events must occur.
In the Venn diagram shown, the area where the circles overlap is P(A and B). What is this area called?
The Joint Probability of A and B
Which of the following is a Conditional Probability?
The chance a high school student will do well in college given the student scored well on the ACT.
Which one of the following conditions must be met to use the Special Rule of Addition? I.e. P(A or B)=P(A) + P(B)
The events A and B must be mutually exclusive.
Select the methodology that would result in a Subjective probability.
Weighing the available information and assigning a probability.
Events are Mutually Exclusive when the occurrence of one event means:
that none of the other events can occur at the same time
Two Events are Independent If...
the occurrence of one event does not change the likelihood that the other will occur
The value given for an Empirical Probability is based on
the past history of outcomes from the experiment
True or false: Prior probability is the initial probability based on the present level of information.
true
Given the following contingency table, how many conditional probabilities are listed for the second set of branches? Assume 'Movies Attended' is represented as the first stage of the tree diagram.
6
The chance of drawing a spade from a deck of cards is 1/4. If the deck is shuffled between draws, what is the probability of drawing two spades in two draws if the first card is returned to the deck between draws?
1/16
Suppose that P(X)=0.20, P(Y)=0.40, P(Z)=0.25, and the events are mutually exclusive. What is the probability of X, Y, or Z occurring?
.85
What is the answer for P(~A) if P(A) = 0.7?
0.3
Using the contingency table shown here, calculate the empirical probability that a randomly chosen person was a man and attended 2 or more movies last month.
1/15
The probability of rolling a one with a die is 1/6. What is the probability of rolling two ones with two dice?
1/36
Given the following contingency table, how many branches go out from the root to the first column? Assume 'Movies Attended' is represented as the first stage of the tree diagram.
3
An urn contains two red and three yellow balls. Two balls are selected randomly without replacement. What is the probability that both are yellow?
6/20
In a probability experiment, what is an outcome?
A particular result of the experiment.
Which of the following statements best describes permutations?
Any arrangement of r objects selected from a single group of n possible objects The order is important
What is the name of a table, such as the one shown, that shows the relationship between two variables?
Contingency table
P(A or B)=P(A) + P(B) For this to be true, which one of the following conditions must be met?
Event A and event B must not be able to occur at the same time,
How is Empirical Probability calculated?
The number of times the event occurs divided by the total number of observations.
Choose the best description of independent events.
The occurrence of one event has no effect on the probability the other will occur.
A bowl contains three red and four yellow marbles. You randomly select two marbles from the bowl. Which of the following is a conditional probability? Assume the second marble is drawn from the marbles remaining after the first draw.
The probability that the second marble will be red, if the first one was yellow.
A set of events is collectively exhaustive when:
at least one of the events must occur when the experiment is done
In the Venn diagram shown, what is the Joint Probability?
P(A and B)
Using the contingency table shown here, calculate the empirical probability that a randomly chosen person was a woman or attended 1 movie last month
4/5