ISDS Final Exam with Complete Solutions
Which statement is true about mutually exclusive events?
a. If either event A or event B must occur, they are called mutually exclusive.
b. P(A) + P(B) = 1 for any events A and B that are mutually exclusive.
c. If events A and B cannot occur at the same time, they are called mutually exclusive.
d. None of these choices are correct. CORRECT ANS-If events A and B cannot occur at the
same time, they are called mutually exclusive.
A joint probability is the
a. sum of the probabilities of two events.
b. sum of the probabilities of two independent events.
c. probability of the intersection of two events.
d. probability of the union of two events. CORRECT ANS-probability of the intersection of
two events.
In the probability table below, which value is a marginal probability?
Completed
Obstacle Course Level
No Yes Total
Challenging 0.4 0.3 0.7
Easy 0.1 0.2 0.3
, ISDS Final Exam with Complete Solutions
Total
0.5 0.5 1.0 CORRECT ANS-0.5
A variable that can only take on specific numeric values is called a
a. discrete random variable.
b. categorical variable.
c. continuous random variable.
d. complex random variable. CORRECT ANS-discrete random variable.
An experiment consists of determining the speed of automobiles on a highway by the use of
radar equipment. The random variable in this experiment is a
a. discrete random variable.
b. categorical random variable.
c. continuous random variable.
d. complex random variable. CORRECT ANS-continuous random variable
Which of the following statements is correct?
a. The binomial and normal distributions are both continuous probability distributions.
b. The binomial distribution is a continuous probability distribution, and the normal
distribution is a discrete probability distribution.
c. The binomial distribution is a discrete probability distribution and the normal distribution
is a continuous probability distribution.
, ISDS Final Exam with Complete Solutions
d. The binomial and normal distributions are both discrete probability distributions.
CORRECT ANS-The binomial distribution is a discrete probability distribution and the
normal distribution is a continuous probability distribution.
Which of the following is a discrete random variable?
a. The amount of gasoline purchased by a customer
b. The height of water-oak trees
c. The amount of mercury found in fish caught in the Gulf of Mexico
d. The number of times a student guesses the answers to questions on a certain test
CORRECT ANS-The number of times a student guesses the answers to questions on a
certain test
All of the following are examples of discrete random variables except
a. marital status.
b. time.
c. number of tickets sold.
d. population of a city. CORRECT ANS-time.
The __________ probability distribution can be used to estimate the number of vehicles that
go through an intersection during the lunch hour.
a. binomial
b. triangular
c. Poisson
, ISDS Final Exam with Complete Solutions
d. normal CORRECT ANS-Poisson
The random variable X is known to be uniformly distributed between 2 and 12. Compute E(X),
the expected value of the distribution.
a. 6
b. 7
c. 4
d. 5 CORRECT ANS-7
The random variable X is known to be uniformly distributed between 2 and 12. Compute the
standard deviation of X.
a. 8.333
b. 12
c. 2.887
d. 3.464 CORRECT ANS-2.887
If a z-score is zero, then the corresponding x-value must be equal to the
a. mode.
b. mean.
c. standard deviation.
d. median. CORRECT ANS-mean.
Which statement is true about mutually exclusive events?
a. If either event A or event B must occur, they are called mutually exclusive.
b. P(A) + P(B) = 1 for any events A and B that are mutually exclusive.
c. If events A and B cannot occur at the same time, they are called mutually exclusive.
d. None of these choices are correct. CORRECT ANS-If events A and B cannot occur at the
same time, they are called mutually exclusive.
A joint probability is the
a. sum of the probabilities of two events.
b. sum of the probabilities of two independent events.
c. probability of the intersection of two events.
d. probability of the union of two events. CORRECT ANS-probability of the intersection of
two events.
In the probability table below, which value is a marginal probability?
Completed
Obstacle Course Level
No Yes Total
Challenging 0.4 0.3 0.7
Easy 0.1 0.2 0.3
, ISDS Final Exam with Complete Solutions
Total
0.5 0.5 1.0 CORRECT ANS-0.5
A variable that can only take on specific numeric values is called a
a. discrete random variable.
b. categorical variable.
c. continuous random variable.
d. complex random variable. CORRECT ANS-discrete random variable.
An experiment consists of determining the speed of automobiles on a highway by the use of
radar equipment. The random variable in this experiment is a
a. discrete random variable.
b. categorical random variable.
c. continuous random variable.
d. complex random variable. CORRECT ANS-continuous random variable
Which of the following statements is correct?
a. The binomial and normal distributions are both continuous probability distributions.
b. The binomial distribution is a continuous probability distribution, and the normal
distribution is a discrete probability distribution.
c. The binomial distribution is a discrete probability distribution and the normal distribution
is a continuous probability distribution.
, ISDS Final Exam with Complete Solutions
d. The binomial and normal distributions are both discrete probability distributions.
CORRECT ANS-The binomial distribution is a discrete probability distribution and the
normal distribution is a continuous probability distribution.
Which of the following is a discrete random variable?
a. The amount of gasoline purchased by a customer
b. The height of water-oak trees
c. The amount of mercury found in fish caught in the Gulf of Mexico
d. The number of times a student guesses the answers to questions on a certain test
CORRECT ANS-The number of times a student guesses the answers to questions on a
certain test
All of the following are examples of discrete random variables except
a. marital status.
b. time.
c. number of tickets sold.
d. population of a city. CORRECT ANS-time.
The __________ probability distribution can be used to estimate the number of vehicles that
go through an intersection during the lunch hour.
a. binomial
b. triangular
c. Poisson
, ISDS Final Exam with Complete Solutions
d. normal CORRECT ANS-Poisson
The random variable X is known to be uniformly distributed between 2 and 12. Compute E(X),
the expected value of the distribution.
a. 6
b. 7
c. 4
d. 5 CORRECT ANS-7
The random variable X is known to be uniformly distributed between 2 and 12. Compute the
standard deviation of X.
a. 8.333
b. 12
c. 2.887
d. 3.464 CORRECT ANS-2.887
If a z-score is zero, then the corresponding x-value must be equal to the
a. mode.
b. mean.
c. standard deviation.
d. median. CORRECT ANS-mean.
