A person’s blood glucose level and diabetes are closely related. Let X be a random variable measured in milligrams of glucose per deciliter (1/10 of a liter) of blood. Suppose that after a 12-hour fast, the random variable X will have a distribution that is approximately normal with mean µ = 90 and standard deviation σ = 20. (Round your answers to three decimal places.)
(A) (3 points) What is the probability that X is greater than 90? (B) (3 points) What is the probability that X is between 70 and 110? (C) (3 points) What is the probability that X is between 55 and 100? (D) (3 points) What is the probability that X is less than 50 or greater than 90? (E) (3 points) What is the probability that X is less than 85?
In: Statistics and Probability
a. Consider the following distribution of a random variable X
|
X |
– 1 |
0 |
1 |
2 |
|
P(X) |
1/8 |
2/8 |
3/8 |
2/8 |
Find the mean, variance and standard deviation
b. There are 6 Republican, 5 Democrat, and 4 Independent candidates. Find the probability the committee will be made of 3 Republicans, 2 Democrats, and 2 Independent be selected?
c. At a large university, the probability that a student takes calculus and is on the dean’s list is 0.042. The probability that a student is on the dean’s list is 0.21. Find the probability that the student is taking calculus given that the student is on the dean’s list.
d. In a statistics class there are 16 juniors and 12 seniors; 8 of the senior students are females, and 12 of the juniors are males. If a student is selected at random, find the probability that the student is neither a junior nor a male.
In: Statistics and Probability
3. Consider the following system made up of functional components in parallel and series.
|
C2 0.80 |
|
C1 0.95 |
|
C3 0.95 |
|
C4 0.80 |
3-1. (2 points) What is the probability that the system operates? Answer: .
3-2. (2 points) What is the probability that the system fails due to the components in series? Assume parallel components do not fail. Answer: .
3-3. (2 points) What is the probability that the system fails due to the components in parallel? Assume series components do not fail. Answer: .
3-4. (2 points) Compute and compare the probabilities that the system fails when the probability that component C1 functions is improved to a value of 0.99 and when the probability that component C3 functions is improved to a value of 0.99. Which improvement increases the system reliability more?
In: Statistics and Probability
According to national data, 20.7% of burglaries are cleared with arrests. A new detective is assigned to six different burglaries. What is the probability that at least one of them is cleared with an arrest?
Consider 4 species of plants in Point of Rocks Park where there are 160 White Pines, 80 Hackberries, 300 Pin Oaks, and 60 Tulip Poplars. What is the probability, and explain how you go about finding the probability, of randomly picking a Pin Oak out of this park.
The probability is . To get the probability, divide by .
Dr. Baum is analyzing the distribution of two genus of trees, Acer and Quercus. In the forest you are currently studying with her, there are 11 species in the genus Acer, while there are 87 species of the genus Quercus. How many possible combinations, consisting of one member from each genus, are possible?
In: Statistics and Probability
When an opinion poll calls landline telephone numbers at random,
approximately 30% of the numbers are working residential phone
numbers. The remainder are either non-residential, non-working, or
computer/fax numbers. You watch the random dialing machine make 20
calls. (Round your answers to four decimal places.)
(a) What is the probability that exactly 4 calls reach working
residential numbers?
(b) What is the probability that at most 4 calls reach working
residential numbers?
(c) What is the probability that at least 4 calls reach working
residential numbers?
(d) What is the probability that fewer than 4 calls reach working
residential numbers?
(e) What is the probability that more than 4 calls reach working
residential numbers?
In: Math
According to a poll on consumer behavior, 36% of people say they will only consider cars manufactured in their country when purchasing a new car. Suppose you select a random sample of 100 respondents. Complete parts (a) through (c) below.
a. What is the probability that the sample will have between 35% and 45% who say they will consider only cars manufactured by a company in their country when purchasing a new car? The probability is 0.5521. (Round to four decimal places as needed.)
b. The probability is 80% that the sample will be contained within what symmetrical limits of the population percentage? The probability is 80% that the sample percentage will be contained above 29.8% and below 42.2%. (Round to one decimal place as needed.)
c. The probability is 68% that the sample will be contained within what symmetrical limits of the population percentage? The probability is 68% that the sample percentage will be contained above 31.2% and below 40.8%. (Round to one decimal place as needed.)
How to solve in excel I already have answers but dont know how to do on excel.
In: Statistics and Probability
Before 1918, approximately 60% of the wolves in the New Mexico and Arizona region were male, and 40% were female. However, cattle ranchers in this area have made a determined effort to exterminate wolves. From 1918 to the present, approximately 65% of wolves in the region are male, and 35% are female. Biologists suspect that male wolves are more likely than females to return to an area where the population has been greatly reduced. (Round your answers to three decimal places.)
(a) Before 1918, in a random sample of 11 wolves spotted in the
region, what is the probability that 8 or more were male?
What is the probability that 8 or more were female?
What is the probability that fewer than 5 were female?
(b) For the period from 1918 to the present, in a random sample of
11 wolves spotted in the region, what is the probability that 8 or
more were male?
What is the probability that 8 or more were female?
What is the probability that fewer than 5 were female?
In: Statistics and Probability
The Aluminum Association reports that the average American uses 56.8 pounds of aluminum in a year. A random sample of 49 households is monitored for one year to determine aluminum usage. If the population standard deviation of annual usage is 12.3 pounds, what is the probability that the sample mean will be each of the following?
Appendix A Statistical Tables
a. More than 60 pounds
b. More than 56 pounds
c. Between 55 and 57 pounds
d. Less than 55 pounds
e. Less than 48 pounds
(Round the values of z to 2 decimal places. Round your
answers to 4 decimal places.)
a. enter the probability that the sample mean will
be more than 60 pounds
b. enter the probability that the sample mean will
be more than 56 pounds
c. enter the probability that the sample mean will
be between 55 and 57 pounds
d. enter the probability that the sample mean will
be less than 55 pounds
e. enter the probability that the sample mean will
be less than 48 pounds
In: Statistics and Probability
The Aluminum Association reports that the average American uses 56.8 pounds of aluminum in a year. A random sample of 50 households is monitored for one year to determine aluminum usage. If the population standard deviation of annual usage is 12.2 pounds, what is the probability that the sample mean will be each of the following?
Appendix A Statistical Tables
a. More than 58 pounds
b. More than 57 pounds
c. Between 56 and 58 pounds
d. Less than 55 pounds
e. Less than 49 pounds
(Round the values of z to 2 decimal places. Round your
answers to 4 decimal places.)
a. enter the probability that the sample mean will
be more than 58 pounds
b. enter the probability that the sample mean will
be more than 57 pounds
c. enter the probability that the sample mean will
be between 56 and 58 pounds
d. enter the probability that the sample mean will
be less than 55 pounds
e. enter the probability that the sample mean will
be less than 49 pounds
In: Statistics and Probability
The following table is a summary of one of the key questions in
the employee satisfaction survey for XYZ Limited. If an employee (a
male) is randomly selected, answer the questions below: (14
points)
| Do you plan to be with Company one year from now? | ||
| Branch | Yes | No |
| Downtown | 45 | 5 |
| Uptown | 87 | 9 |
In: Statistics and Probability