IEE 380 Exam 1 Questions and Correct Answers
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.
0.0408
When we plot _____________, we see "blades of grass."
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.
0.896
P(A∪B) + P(A∩B) = P(A) + ____
P(B)
In the Binomial pmf, the letter p (the one appearing on the right side of the equals sign)
is
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
False
If X is a discrete random variable, P(3 < X < 7) may be expressed as: 1. F(6) - F(3) 2.
p(3) + p(5) + p(6)
True/False
True
If we want to determine the pdf from a CDF for a continuous random variable, we
_________ the CDF.
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.
0.0408
When we plot _____________, we see "blades of grass."
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.
0.896
P(A∪B) + P(A∩B) = P(A) + ____
P(B)
In the Binomial pmf, the letter p (the one appearing on the right side of the equals sign)
is
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
False
If X is a discrete random variable, P(3 < X < 7) may be expressed as: 1. F(6) - F(3) 2.
p(3) + p(5) + p(6)
True/False
True
If we want to determine the pdf from a CDF for a continuous random variable, we
_________ the CDF.
