Quiz 3
The "Top Three" at a racetrack consists of picking the correct order of the first three horses in a race. If there are 10 horses in a particular race, how many "Top Three" outcomes are there?
720
Each customer entering a department store will either buy or not buy some merchandise. An experiment consists of following 3 customers and determining whether or not they purchase any merchandise. The number of sample points in this experiment is
8
Posterior probabilities are computed using
Bayes' Theorem
In statistical experiments, each time the experiment is repeated
a different outcome may occur
A graphical method of representing the sample points of a multiple-step experiment is
a tree diagram
Any process that generates well-defined outcomes is
an experiment
Two events with nonzero probabilities
can not be both mutually exclusive and independent
In an experiment, events A and B are mutually exclusive. If P(A) = 0.6, then the probability of B
cannot be larger than .4
A method of assigning probabilities that assumes the experimental outcomes are equally likely is referred to as the
classical method
When the assumption of equally likely outcomes is used to assign probability values, the method used to assign probabilities is referred to as the
classical method
One of the basic requirements of probability is
if there are k experimental outcomes, then P(E1) + P(E2) + ... + P(Ek) = 1
If P(A) = 0.50, P(B) = 0.60, and P(A ∩ B) = 0.30; then events A and B are
independent events
The probability of the occurrence of event A in an experiment is 1/3. If the experiment is performed 2 times and event A did not occur, then on the third trial event A
may occur
Events that have no sample points in common are
mutually exclusive events
Assume your favorite football team has 2 games left to finish the season. The outcome of each game can be win, lose or tie. The number of possible outcomes is
none of the answers are correct
Revised probabilities of events based on additional information are
posterior probabilities
The multiplication law is potentially helpful when we are interested in computing the probability of
the intersection of two events
Bayes' theorem is used to compute
the posterior probabilities
The collection of all possible sample points in an experiment is
the sample space
The sample space refers to
the set of all possible experimental outcomes
The addition law is potentially helpful when we are interested in computing the probability of
the union of two events
If A and B are independent events with P(A) = 0.38 and P(B) = 0.55, then P(A∩B) =
unknown
If P(A|B) = .3,
unknown
Which of the following statements is(are) always true?
unknown
On a December day, the probability of snow is .30. The probability of a "cold" day is .50. The probability of snow and a "cold" day is .15. Are snow and "cold" weather independent events?`
yes
Two events, A and B, are mutually exclusive and each has a nonzero probability. If event A is known to occur, the probability of the occurrence of event B is
zero
The range of probability is
zero to one
If A and B are mutually exclusive events with P(A) = 0.3 and P(B) = 0.5, then P(A ∩ B) =
0.00
If X and Y are mutually exclusive events with P(X) = 0.295, P(Y) = 0.32, then P(X⏐Y) =
0.00
If a coin is tossed three times, the likelihood of obtaining three heads in a row is
.125
If A and B are mutually exclusive events with P(A) = 0.3 and P(B) = 0.5, then P(A ∪ B) =
.15
If P(A) = 0.62, P(B) = 0.47, and P(A ∪ B) = 0.88; then P(A ∩ B) =
.2100
If A and B are independent events with P(A) = 0.4 and P(B) = 0.6, then P(A ∩ B) =
.24
If a penny is tossed four times and comes up heads all four times, the probability of heads on the fifth trial is
.5
Of the last 100 customers entering a computer shop, 25 have purchased a computer. If the classical method for computing probability is used, the probability that the next customer will purchase a computer is
.50
If P(A) = 0.38, P(B) = 0.83, and P(A ∩ B) = 0.57; then P(A ∪ B) =
.64
If A and B are independent events with P(A) = 0.2 and P(B) = 0.6, then P(A ∪ B) =
.68
A lottery is conducted using three urns. Each urn contains chips numbered from 0 to 9. One chip is selected at random from each urn. The total number of sample points in the sample space is
1,000
A six-sided die is tossed 3 times. The probability of observing three ones in a row is
1/216
Of five letters (A, B, C, D, and E), two letters are to be selected at random. How many possible selections are there?
10
An experiment consists of tossing 4 coins successively. The number of sample points in this experiment is
16
An experiment consists of three steps. There are four possible results on the first step, three possible results on the second step, and two possible results on the third step. The total number of experimental outcomes is
24
The probability of the intersection of two mutually exclusive events
Must always be equal to 0
A graphical device used for enumerating sample points in a multiple-step experiment is a
None of the answers are correct
Since the sun must rise tomorrow, then the probability of the sun rising tomorrow is
None of the answers are correct
Events A and B are mutually exclusive with P(A) = 0.3 and P(B) = 0.2. The probability of the complement of Event B equals
None of the other answers are Correct
A method of assigning probabilities based upon judgment is referred to as the
None of the other answers are correct
A perfectly balanced coin is tossed 6 times and tails appears on all six tosses. Then, on the seventh trial
None of the other answers are correct
The probability of the union of two events with nonzero probabilities
None of the other answers is correct
The complement of P(A | B) is
P(Ac | B)
