ORMS 3310 CH 3

To calculate the probability of the union of two mutually exclusive events A and B,

we add the probability of A to the probability of B.

Probability values range from

zero to one.

The total probability rule is used to compute the probability of an event by using

joint probabilities. conditional probabilities.

A probability based on personal judgment rather than on observation or logical analysis is best referred to as a(n)

subjective probability.

The addition rule for two events A and B is

P(A) + P(B) - P(A∩B)

If A and B are independent events, then

P(A) = P(A|B)

The complement rule with respect to event A is

P(AC) = 1 - P(A)

For two events A and B, the multiplication rule is

P(A∩B) = P(A|B) × P(B).

How would you express the probability that a customer at the movie theater will order a drink (D) given that the customer orders popcorn (P)?

P(D|P)

Kareem is trying to decide which college to attend full-time next year. Kareem believes there is a 55% chance that he will attend State College and a 33% chance that he will attend Northern University. The probability that Kareem will attend either State or Northern is ______ .

0.88

What assumption is made with classical method of determining probabilities?

All outcomes are equally likely.

When rolling a pair of dice and summing the two values rolled, which of the following are exhaustive events? Select all that apply

An even number and an odd number. A sum of 7 or more and a sum of 6 or less. A sum of 6 or more and a sum of 8 or less.

The conditional probability of A given B is calculated by dividing the probability of intersection of A and B by the probability of

B.

When considering the union of two events, A and B, which ones of the following would be included? Select all that apply.

The outcomes that form event B. The outcomes that are in both events A and B. The outcomes that form event A.

Which of the following is an example of a conditional probability?

The probability that Lisa passes the test, given that she attends class and does the homework.

A probability based on logical analysis rather than on observation or personal judgment is BEST referred to as a(n):

classical

For hotels in New York City, a travel web site wants to provide information comparing hotel costs (high, average, low) versus the quality ranking of the hotel (excellent, good, fair, poor). A useful way to summarize these data is to construct a(n)

contingency table.

A subset of the sample space is called a/an

event

The fact that an empirical probability will approach the classical probability if an experiment is conducted many times is known as the

law of large numbers.

IThe values shown in the last row (Total) or last column (Total) of a joint probability table are called

marginal probabilities.

The addition rule is used to calculate

the union of two events.

For any given event, the probability of that event and the probability of the complement of the event must sum to

1.0

When constructing a joint probability table, the cell in the lower right corner must always equal

1.0

Which method(s) can be used to help implement the total probability rule? Select all that apply.

A probability tree Tabular method.

Why does the addition rule for mutually exclusive events not subtract the intersection of the two events?

Because their intersection is 0.

Which of the following is NOT an example of an experiment

Determine a historical fact such as the name of the U.S. President in the year 1856.

Which one of the following words is associated with the union of two events?

Or

Sometimes the union of two events will be overstated if the union is found by adding just the individual probabilities. What is done to keep from overstating the probability of the union of two events?

The intersection of the event is subtracted.

If an experiment is selecting a card from a deck of cards, then the sample space is

all the cards in the deck.

A ______ probability is the probability of an event given that another event has already occurred.

conditional

Mutually exclusive and exhaustive events

contain all outcomes in an experiment and do not share common outcomes.

The probability of a student passing the CPA exam is 0.60. The probability of a student passing the exam given the student takes the prep course is 0.80. The events passing the exam and taking the prep course are

dependent.

Mutually exclusive events

do not share common outcomes of the experiment.

Using the multiplication rule, the probability that event A and event B both occur is computed by multiplying the conditional probability of event A given event B by the probability of

event B.

Events that include all outcomes in the sample space are known as ______ events

exhaustive

If two events do not influence each other, then the events are ______ events.

independent

Based on past data, the probability that a new hire at Company XYZ will be successful is 0.70. The company has started using an applicant screening test. Given the applicant scores well on the test, the probability the new hire will be successful is 0.70. The events 'new hire being successful' and 'applicant scoring well' are

independent.

The probability that a customer will purchase a product is 0.20. The probability that a customer is a male is 0.5. The probability that a customer is a male and will purchase a product is 0.10. The events of purchasing a product and being a male are

independent.

The values shown in interior of a joint probability table (not the last rows or columns) are called

joint probabilities.

The values shown in the last row (Total) or last column (Total) of a joint probability table are called

marginal probabilities.

The sum of the probabilities of a list of mutually exclusive and collectively exhaustive events is

one.

If two events are independent, then the probability that both events occur equals

the product of the individual probabilities.

In order to convert a contingency table into a joint probability table, the frequency of each cell is divided by the

total number of outcomes in the sample space.

in order to convert a contingency table into a joint probability table, the frequency of each cell is divided by the

total number of outcomes in the sample space.

Contingency tables are useful to analyze

two categorical variables.