In: Statistics and Probability
A university conducted a survey of
381
undergraduate students regarding satisfaction with student government. Results of the survey are shown in the table by class rank. Complete parts (a) through (d) below.
Freshman Sophomore
Junior Senior
Satisfied 54 48 64 60
Neutral 30 20 17 14
Not satisfied 25 19
10 20
(a) If a survey participant is selected at random, what is the probability that he or she is satisfied with student government?
(b) If a survey participant is selected at random, what is the probability that he or she is a junior?
(c) If a survey participant is selected at random, what is the probability that he or she is satisfied and a junior?
(d) If a survey participant is selected at random, what is the probability that he or she is satisfied or a junior?
In: Statistics and Probability
|
Make an A |
Make a B |
Make a C |
Make a D |
Make an F |
|
|
Sophomores |
.058 |
.101 |
.142 |
.092 |
.047 |
|
Juniors |
.055 |
.082 |
.102 |
.071 |
.030 |
|
Seniors |
.014 |
.023 |
.080 |
.063 |
.040 |
(a) What is the probability that a randomly selected student in Dr. Alan Math course is a Sophomore?
(b) What is the probability that a randomly selected student will make a D in Dr. Alan Math course?
(c) Given that a particular student made a B or better in Dr. Alan Math course, what is the probability that he or she took the course as a Junior?
(d) Given that a particular student in Dr. Alan Math course is a Senior, what is the probability that he or she will make an A in the course?
In: Statistics and Probability
Brady is a figure skater. He finds a few of the jumps he does to
be difficult, but the rest are easy for him. He must include four
jumps in his routine. He always makes the first jump a difficult
one. After a difficult jump, there is a 0.4 probability that he'll
do another difficult jump, and otherwise he'll do an easy one.
After an easy jump, there is a 0.2 probability that he'll do
another easy one, and otherwise he'll do a hard
one.
What is the probability that the final (fourth) jump of his routine
will be an easy one?
What is the probability that all four jumps of his routine will be
difficult ones?
Enter your answers as whole numbers or decimals.
In: Advanced Math
Customers arrive at a department store according to a Poisson process with an average of 12 per hour.
a. What is the probability that 3 customers arrive between 12:00pm and 12:15pm?
b. What is the probability that 3 customers arrive between 12:00pm and 12:15pm and 6 customers arrive between 12:30pm and 1:00pm?
c. What is the probability that 3 customers arrive between 12:00pm and 12:15pm or 6 customers arrive between 12:30pm and 1:00pm?
d. What is the probability that a total of 10 customers arrive between 12:00pm and 12:15pm and 12:45pm and 1:00pm? That is, the total count is 10 for both of these time intervals combined.
In: Statistics and Probability
The probability that a randomly selected 2 -year-old male chipmunk will live to be 3 years old is 0.98632 . (a) What is the probability that two randomly selected 2 -year-old male chipmunk s will live to be 3 years old? (b) What is the probability that nine randomly selected 2 -year-old male chipmunk s will live to be 3 years old? (c) What is the probability that at least one of nine randomly selected 2 -year-old male chipmunk s will not live to be 3 years old? Would it be unusual if at least one of nine randomly selected 2 -year-old male chipmunk s did not live to be 3 years old?
In: Statistics and Probability
Problem 2.2 Consider a production system consisting of three
Bernoulli
machines and a controller, which also obeys the Bernoulli
reliability model. This
production system is considered up if the controller and at least
two machines are
up. During each cycle, the controller is up with probability 0.8
and each machine
is up with probability 0.9. The controller and the machines fail
independently.
(a) Calculate the probability that the production system is
up.
(b) Assume that a second controller, identical to the first one, is
added to the
system, and the re-designed system is up if at least one controller
and two
machines are up. Calculate the probability that the re-designed
production
system is up.
(c) Explain the reason for the difference between the two numbers
you calculated.
In: Statistics and Probability
Assume that females have pulse rates that are normally distributed with a mean of
mu equals 74.0μ=74.0
beats per minute and a standard deviation of
sigma equals 12.5σ=12.5
beats per minute. Complete parts (a) through (c) below.
a. If 1 adult female is randomly selected, find the probability that her pulse rate is between
70 beats per minute and 78
beats per minute.
A) The probability is .2510
(Round to four decimal places as needed.)
b. If 16 adult females are randomly selected, find the probability that they have pulse rates with a mean between
70 beats per minute and 78 beats per minute.The probability is________
(Round to four decimal places as needed.)
In: Statistics and Probability
In an urn, there are 5 red balls, 5 green balls, 4 yellow balls, and 6 white balls. You are drawing balls without replacement.
a. When you draw the first ball, what is the probability that the ball will be white?
b. Let us assume that you have drawn two balls and both of them are green. What is the probability that the next ball drawn will be green?
c. Let us assume that the third ball drawn is also green like the first two balls. What is the probability that the fourth ball drawn is white?
d. Let us assume that a fourth ball is drawn, but the color is not revealed to you. What is the probability that the fifth ball drawn is white?
In: Statistics and Probability
There are two types of potential borrowers in equal numbers among the population. All have projects that require an investment of $100, which must be borrowed. Type A projects yield a gross return of $130 in one year with probability .8; they fail and yield 0 with probability .2. Type B projects yield a gross rate of return of $250 with probability .4, but fail, yielding zero, with probability .6. Potential lenders require a gross return of $102 on $100 loaned. With symmetric information, who will get financing and why? Now suppose the project expected returns are private information. Lenders cannot distinguish one type from another. Will any lending occur? Why or why not? Explain in detail.
In: Economics