IEE 380 EXAM 1+2 QUESTIONS & 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. - Answer -0.0408
When we plot _____________, we see "blades of grass." - 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. - Answer -0.896
P(A∪B) + P(A∩B) = P(A) + ____ - Answer -P(B)
In the Binomial pmf, the letter p (the one appearing on the right side of the equals sign)
is - 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 - Answer -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 - Answer -True
If we want to determine the pdf from a CDF for a continuous random variable, we
_________ the CDF. - Answer -differentiate
What is the text notation for the probability density function of a continuous random
variable, X? - Answer -f(x)
X is the number of earthquakes in a year. X is known to be Poisson with a mean equal
to 3.6 earthquakes per year. What is the probability that the number of earthquakes in 2
years is equal to 5? Enter your answer to four decimal places using conventional
rounding methods. - Answer -0.1204
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. - Answer -0.0408
When we plot _____________, we see "blades of grass." - 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. - Answer -0.896
P(A∪B) + P(A∩B) = P(A) + ____ - Answer -P(B)
In the Binomial pmf, the letter p (the one appearing on the right side of the equals sign)
is - 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 - Answer -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 - Answer -True
If we want to determine the pdf from a CDF for a continuous random variable, we
_________ the CDF. - Answer -differentiate
What is the text notation for the probability density function of a continuous random
variable, X? - Answer -f(x)
X is the number of earthquakes in a year. X is known to be Poisson with a mean equal
to 3.6 earthquakes per year. What is the probability that the number of earthquakes in 2
years is equal to 5? Enter your answer to four decimal places using conventional
rounding methods. - Answer -0.1204
