IEE 380 EXAM 2025/2026 QUESTIONS
AND ANSWERS 100% PASS
Historical data is used if you are doing a _________ study. - ANS Retrospective
If you go out to collect data to analyze, this would be an example of a ________ study. -
ANS observational
The Addition Rule states that P(A U B) = P(A) + P(B) - _________. - ANS P(A∩B)
The variance formula for a random variable with the Discrete Uniform pmf will only work if the
values of the random variable are __________ integers. - ANS Consecutive
Recall that in class, we talked about discrete and continuous random variables. Which of the
follwoing would be a good example of a continuous random variable?
a) Number of defects on a circuit board.
b) Number of cars passing in an intersection.
c) A student's GPA as reported on their transcript.
d) The face value for the throw of a fair die.
e) The height of a person - ANS Height
Consider a discrete random variable. Which of the following, when plotted will look like stairs
going up and to the right? - ANS F(X)
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, Consider a discrete random variable X, with range x= 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. P(X < 10) = F(
). What number should be in the parenthesis after "F"? - ANS 9
Width measuremetns of a steel bar are made to the nearest hundreth of a millimeter. The
thickness measurements are discrete uniformly distributed with values 1mm, 2mm, 3mm, and
4mm. E(X) = 2.5 mm.
a) What is the expected value of a discrete random variable, X.
b) What is the units? - ANS a) 2.5
b) mm
Which of the following probability distributions often determines the probabilities of a counting
process? - ANS Poisson Distribution
An electronic product contains 51 integrated circuits. The probability that any integrated circuit
is defective is 0.01, and the integrated circuits are independent. Suppose you want to
determine the probability that the number of defective circuits in this product is equal to 2. The
best definition of the random variable, X, in words is: - ANS X is the number of defective
integrated circuits out of 51 integrated circuits.
Explanation: X is a binomial random variable, not a probability.
We know that ________ will always have one of two outcomes. - ANS A Bernoulli Trial
A side door panel on a vehicle is produced at Acme Co. Twenty-five of these doors are
inspected to determine if they pass or fail. The probability that a door passes is 0.83. Suppose
you want to determine the probability that the number of doors that pass our of these 25 is
equal to 19. The best definition of the random variable, X, in words is: - ANS X is the number
of doors out of 25 that pass.
p(x) is the notation for pmf of a discrete random variable. We also know that F(X) is the
notation for a CDF, the cumulative distribtuion function. If X is a discrete random variable, what
is true?
a) F(X) >= p(X)
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
AND ANSWERS 100% PASS
Historical data is used if you are doing a _________ study. - ANS Retrospective
If you go out to collect data to analyze, this would be an example of a ________ study. -
ANS observational
The Addition Rule states that P(A U B) = P(A) + P(B) - _________. - ANS P(A∩B)
The variance formula for a random variable with the Discrete Uniform pmf will only work if the
values of the random variable are __________ integers. - ANS Consecutive
Recall that in class, we talked about discrete and continuous random variables. Which of the
follwoing would be a good example of a continuous random variable?
a) Number of defects on a circuit board.
b) Number of cars passing in an intersection.
c) A student's GPA as reported on their transcript.
d) The face value for the throw of a fair die.
e) The height of a person - ANS Height
Consider a discrete random variable. Which of the following, when plotted will look like stairs
going up and to the right? - ANS F(X)
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, Consider a discrete random variable X, with range x= 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. P(X < 10) = F(
). What number should be in the parenthesis after "F"? - ANS 9
Width measuremetns of a steel bar are made to the nearest hundreth of a millimeter. The
thickness measurements are discrete uniformly distributed with values 1mm, 2mm, 3mm, and
4mm. E(X) = 2.5 mm.
a) What is the expected value of a discrete random variable, X.
b) What is the units? - ANS a) 2.5
b) mm
Which of the following probability distributions often determines the probabilities of a counting
process? - ANS Poisson Distribution
An electronic product contains 51 integrated circuits. The probability that any integrated circuit
is defective is 0.01, and the integrated circuits are independent. Suppose you want to
determine the probability that the number of defective circuits in this product is equal to 2. The
best definition of the random variable, X, in words is: - ANS X is the number of defective
integrated circuits out of 51 integrated circuits.
Explanation: X is a binomial random variable, not a probability.
We know that ________ will always have one of two outcomes. - ANS A Bernoulli Trial
A side door panel on a vehicle is produced at Acme Co. Twenty-five of these doors are
inspected to determine if they pass or fail. The probability that a door passes is 0.83. Suppose
you want to determine the probability that the number of doors that pass our of these 25 is
equal to 19. The best definition of the random variable, X, in words is: - ANS X is the number
of doors out of 25 that pass.
p(x) is the notation for pmf of a discrete random variable. We also know that F(X) is the
notation for a CDF, the cumulative distribtuion function. If X is a discrete random variable, what
is true?
a) F(X) >= p(X)
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
