IEE 380 Exam 1 Question and answers
rated A+ 2025/2026
Let the random variable X denote the number of the 48 voice lines that are in use at a particular time.
Assume that X is a discrete uniform random variable with a range of 0 to 48. What is the probability that
the number of voice lines in use at a particular time is more than 46? Use conventional Rounding
methods. - correct answer ✔0.0408
When we plot _____________, we see "blades of grass." - correct answer ✔the pmf of a discrete
random variable
The time to recharge the flash is tested in three cell-phone cameras. The probability that a camera
passes the test is 0.8, and the cameras perform independently. What is the probability that the number
of cameras that pass the test is more than 1? Round to 3 decimal places. - correct answer ✔0.896
P(A∪B) + P(A∩B) = P(A) + ____ - correct answer ✔P(B)
In the Binomial pmf, the letter p (the one appearing on the right side of the equals sign) is - correct
answer ✔the probability of "success" of each Bernoulli trial
Samples of water are taken from 18 different locations. Each sample of water has a 10% chance of
containing a particular organic pollutant. Assume that the samples are independent with regard to the
presence of the pollutant. If we want to determine the probability that more than 6 samples contain the
pollutant, the definition of our random variable will be:
X is the probability that more than 6 samples contain the pollutant
True/False - correct answer ✔False
rated A+ 2025/2026
Let the random variable X denote the number of the 48 voice lines that are in use at a particular time.
Assume that X is a discrete uniform random variable with a range of 0 to 48. What is the probability that
the number of voice lines in use at a particular time is more than 46? Use conventional Rounding
methods. - correct answer ✔0.0408
When we plot _____________, we see "blades of grass." - correct answer ✔the pmf of a discrete
random variable
The time to recharge the flash is tested in three cell-phone cameras. The probability that a camera
passes the test is 0.8, and the cameras perform independently. What is the probability that the number
of cameras that pass the test is more than 1? Round to 3 decimal places. - correct answer ✔0.896
P(A∪B) + P(A∩B) = P(A) + ____ - correct answer ✔P(B)
In the Binomial pmf, the letter p (the one appearing on the right side of the equals sign) is - correct
answer ✔the probability of "success" of each Bernoulli trial
Samples of water are taken from 18 different locations. Each sample of water has a 10% chance of
containing a particular organic pollutant. Assume that the samples are independent with regard to the
presence of the pollutant. If we want to determine the probability that more than 6 samples contain the
pollutant, the definition of our random variable will be:
X is the probability that more than 6 samples contain the pollutant
True/False - correct answer ✔False
