Probability

Question 1

Each individual outcome of an experiment is called

Answer 1

a sample point

Question 2

A graphical method of representing the sample points of an experiment is

Answer 2

a tree diagram

Question 3

Any process that generates well-defined outcomes is

Answer 3

an experiment

Question 4

In statistical experiments, each time the experiment is repeated

Answer 4

a different outcome may occur

Question 5

The counting rule that is used for counting the number of experimental outcomes when n objects are selected from a set of N objects where order of selection is not important is called

Answer 5

combination

Question 6

From a group of six people, two individuals are to be selected at random. How many possible selections are there?

Answer 6

15

Question 7

A method of assigning probabilities based upon judgment is referred to as the

Answer 7

subjective method

Question 8

A graphical device used for enumerating sample points in a multiple-step experiment is a

Answer 8

not a bar chart, a pie chart nor a histogram

Question 9

The set of all possible outcomes of an experiment is

Answer 9

the sample space

Question 10

If a dime is tossed four times and comes up tails all four times, the probability of heads on the fifth trial is

Answer 10

1/2

Question 11

Of five letters (A, B, C, D, and E), two letters are to be selected at random. How many possible selections are there?

Answer 11

10

Question 12

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

Answer 12

9

Question 13

An experiment consists of tossing 4 coins successively. The number of sample points in this experiment is

Answer 13

16

Question 14

Since the sun must rise tomorrow, then the probability of the sun rising tomorrow is

Answer 14

not much larger than zero, zero nor infinity

Question 15

If a coin is tossed three times, the likelihood of obtaining three heads in a row is

Answer 15

0.125

Question 16

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

Answer 16

0.50

Question 17

A six-sided die is tossed 3 times. The probability of observing three ones in a row is

Answer 17

1/216

Question 18

A perfectly balanced coin is tossed 6 times and tails appears on all six tosses. Then, on the seventh trial

Answer 18

both heads and tails can appear

Question 19

A method of assigning probabilities which assumes that the experimental outcomes are equally likely is referred to as the

Answer 19

classical method

Question 20

The probability assigned to each experimental outcome must be

Answer 20

between zero and one

Question 21

Some of the CDs produced by a manufacturer are defective. From the production line, 5 CDs are selected and inspected. How many sample points exist in this experiment?

Answer 21

32

Question 22

Assume your favorite football team has 3 games left to finish the season. The outcome of each game can be win, lose, or tie. How many possible outcomes exist?

Answer 22

27

Question 23

From nine cards numbered 1 through 9, two cards are drawn. Consider the selection and classification of the cards as odd or even as an experiment. How many sample points are there for this experiment?

Answer 23

4

Question 24

If a six sided die is tossed two times, the probability of obtaining two “4s” in a row is

Answer 24

1/36

Question 25

The intersection of two mutually exclusive events

Answer 25

must always be equal to 0

Question 26

The range of probability is

Answer 26

zero to one

Question 27

Two events, A and B, are mutually exclusive and each have a nonzero probability. If event A is known to occur, the probability of the occurrence of event B is

Answer 27

zero

Question 28

The sum of the probabilities of two complementary events is

Answer 28

1.0

Question 29

One of the basic requirements of probability is

Answer 29

if there are k experimental outcomes, then sumP(Ei) = 1

Question 30

The symbol 'or' shows the

Answer 30

union of events

Question 31

The union of events A and B is the event containing

Answer 31

all the sample points belonging to A or B or both

Question 32

If A and B are mutually exclusive events with P(A) = 0.3 and P(B) = 0.5, then P(A 'and' B) =

Answer 32

0.00

Question 33

Events A and B are mutually exclusive with P(A) = 0.3 and P(B) = 0.2. Then, P(B to the power of c) =

Answer 33

0.8

Question 34

In an experiment, events A and B are mutually exclusive. If P(A) = 0.6, then the probability of B

Answer 34

cannot be larger than 0.4

Question 35

If P(A) = 0.62, P(B) = 0.47, and P(A 'or' B) = 0.88, then P(A 'and' B) =

Answer 35

0.2100

Question 36

If P(A) = 0.7, P(B) = 0.6, P(A 'and' B) = 0, then events A and B are

Answer 36

mutually exclusive

Question 37

Two events with nonzero probabilities

Answer 37

can not be both mutually exclusive and independent

Question 38

If A and B are independent events with P(A) = 0.65 and P(A 'and' B) = 0.26, then, P(B) =

Answer 38

0.400

Question 39

If two events are independent, then

Answer 39

they must not be mutually exclusive, the sum of their probabilities must not be equal to one and their intersection must not be zero

Question 40

The multiplication law is potentially helpful when we are interested in computing the probability of

Answer 40

the intersection of two events

Question 41

If A and B are independent events with P(A) = 0.4 and P(B) = 0.6, then P(A 'and' B) =

Answer 41

0.24

Question 42

If A and B are independent events with P(A) = 0.05 and P(B) = 0.65, then P(A | B) =

Answer 42

0.05

Question 43

If A and B are independent events with P(A) = 0.4 and P(B) = 0.25, then P(A 'or' B) =

Answer 43

0.55

Question 44

If A and B are independent events with P(A) = 0.38 and P(B) = 0.55, then P(A | B) =

Answer 44

0.38

Question 45

If A and B are independent events with P(A) = 0.35 and P(B) = 0.20, then, P(A 'or' B) =

Answer 45

0.48