A researcher has collected the blood samples of 30 individuals and found that the mean hemoglobin concentration for the sample of individuals is 13.9 grams per deciliter and the standard deviation is 1.43 grams per deciliter. Calculate a 99.0% confidence interval for the mean hemoglobin concentration for the population.

[1] (10.22, 17.58)

[2] (13.17, 14.63)

[3] (13.18, 14.62)

[4] (13.23, 14.57)

Course: Marketing Management

For a product of your own choosing, pick one logical variable (e.g., age) that can be used to segment the market. Now add a second variable (e.g., gender) so that customers have to satisfy the categories of both variables simultaneously (e.g., 18 - to 24 year old women).Now add a third variable. How many possiblesignments can you identify from a combination of three variables? What implications does this have for the marketing manager?

Harper's Index reported that the number of (Orange County, California) convicted drunk drivers whose sentence included a tour of the morgue was 542, of which only 1 became a repeat offender.

(a) Suppose that of 1074 newly convicted drunk drivers, all were required to take a tour of the morgue. Let us assume that the probability of a repeat offender is still p = 1/542. Explain why the Poisson approximation to the binomial would be a good choice for r = number of repeat offenders out of 1074 convicted drunk drivers who toured the morgue.

The Poisson approximation is good because n is large, p is small, and np < 10.The Poisson approximation is good because n is large, p is small, and np > 10.     The Poisson approximation is good because n is large, p is large, and np < 10.The Poisson approximation is good because n is small, p is small, and np < 10.

What is λ to the nearest tenth?


(b) What is the probability that r = 0? (Use 4 decimal places.)


(c) What is the probability that r > 1? (Use 4 decimal places.)


(d) What is the probability that r > 2? (Use 4 decimal places.)


(e) What is the probability that r > 3? (Use 4 decimal places.)

Bob is a recent law school graduate who intends to take the state bar exam. According to the National Conference on Bar Examiners, about 48% of all people who take the state bar exam pass. Let n = 1, 2, 3, ... represent the number of times a person takes the bar exam until the first pass.

(a) Write out a formula for the probability distribution of the random variable n. (Use p and n in your answer.)
P(n) =  

(b) What is the probability that Bob first passes the bar exam on the second try (n = 2)? (Use 3 decimal places.)


(c) What is the probability that Bob needs three attempts to pass the bar exam? (Use 3 decimal places.)


(d) What is the probability that Bob needs more than three attempts to pass the bar exam? (Use 3 decimal places.)


(e) What is the expected number of attempts at the state bar exam Bob must make for his (first) pass? Hint: Use μ for the geometric distribution and round.

Study the binomial distribution table. Notice that the probability of success on a single trial p ranges from 0.01 to 0.95. Some binomial distribution tables stop at 0.50 because of the symmetry in the table. Let's look for that symmetry. Consider the section of the table for which n = 5. Look at the numbers in the columns headed by p = 0.30 and p = 0.70. Do you detect any similarities? Consider the following probabilities for a binomial experiment with five trials.

(a) Compare P(3 successes), where p = 0.30, with P(2 successes), where p = 0.70.

P(3 successes), where p = 0.30, is smaller.They are the same.     P(3 successes), where p = 0.30, is larger.

(b) Compare P(3 or more successes), where p = 0.30, with P(2 or fewer successes), where p = 0.70.

P(3 or more successes), where p = 0.30, is smaller.They are the same.     P(3 or more successes), where p = 0.30, is larger.

(c) Find the value of P(4 successes), where p = 0.30. (Round your answer to three decimal places.)
P(4 successes) =  

For what value of r is P(r successes) the same using p = 0.70?
r =  

(d) What column is symmetrical with the one headed by p = 0.20?

the column headed by p = 0.85the column headed by p = 0.80     the column headed by p = 0.40the column headed by p = 0.50the column headed by p = 0.70

Smitley and Davis studied the changes in gypsy moth egg mass density over one generation as a function of the initial egg mass density in a control plot and two treated plots. The data below are for the control plot.

A. On the basis of the data given in the table, find the best-fitting logarithmic function using least squares. State the square of the correlation coefficient. (Note that the authors used logarithms to the base 10.) (Use 4 decimal places in your answers.)
y(x) =

r² =

B. Use this model to estimate the change in egg mass density with an initial egg mass of 120 per 0.04 ha. (Use 4 decimal places in your answer.)
With an initial egg mass of 120 per 0.04ha, the change in mass density is

%

Question 1 2 pts

In a sample of 80 adults, 28 said that they would buy a car from a friend. Three adults are selected at random without replacement. Find the probability that none of the three would buy a car from a friend.

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Question 2 2 pts

A sock drawer has 17 folded pairs of socks, with 8 pairs of white, 5 pairs of black and 4 pairs of blue. What is the probability, without looking in the drawer, that you will first select and remove a black pair, then select either a blue or a white pair?

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Question 3 2 pts

An investment advisor believes that there is a 60% chance of making money by investing in a specific stock. If the stock makes money, then there is a 50% chance that among those making money, they would also get a dividend. Find the probability that the investor makes money and receive a dividend.

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Question 4 2 pts

An investment advisor believes that there is a 60% chance of making money by investing in a specific stock. If the stock makes money, then there is a 50% chance that among those making money, they would also get a dividend. Find the probability that the investor makes money and receive a dividend.

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Question 5 2 pts

A smartphone company found in a survey that 6% of people did not own a smartphone, 15% owned a smartphone only, 26% owned a smartphone and only a tablet, 32% owned a smartphone and only a computer, and 21% owned all three. If a person were selected at random, what is the probability that the person would own a smartphone only or a smartphone and computer?

Which of the following statements are TRUE?

Note that there may be more than one correct answer; select all that are true.

There are countably infinite values of X in a continuous uniform distribution.

For a continuous uniform distribution defined on the interval [a,b], P(X < a) and P(X > b) is undefined.

The mean and the variance of a continuous uniform random variable are the same.

In a continuous uniform distribution, the mean and the median are the same.

In a continuous uniform distribution, the height of the curve, f(x), is the same for all values of the random variable X.

1a) Assume we're working with normally distributed SAT scores, with the following distribution: Mean = 500 and Std. Dev = 100. A student is randomly selected from the SAT population. What's the probability of that student's score being between 350 and 600?

1b) Assume we're working with normally distributed SAT scores, with the following distribution: Mean = 500 and Std. Dev = 100. A college decides to admit students with SAT scores greater than or equal to 450. Assuming the applicant population contains 1500 students, how many would be admitted?

1c) Assume we're working with normally distributed SAT scores, with the following distribution: Mean = 500 and Std. Dev = 100. A college decides to admit only the top 10% of SAT students. What would its cutoff SAT score be?

The method of tree ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population of x values has an approximately normal distribution.

(a) Use a calculator with mean and standard deviation keys to find the sample mean year x and sample standard deviation s. (Round your answers to the nearest whole number.)

(b) Find a 90% confidence interval for the mean of all tree ring dates from this archaeological site. (Round your answers to the nearest whole number.)

Formulate the indicated conclusion in nontechnical terms. Be sure to address the original claim. A skeptical paranormal researcher claims that the proportion of Americans that have seen a UFO, p, is less than 1 in every ten thousand. Assuming that a hypothesis test of the claim has been conducted and that the conclusion is failure to reject the null hypothesis, state the conclusion in nontechnical terms

The following table contains observed frequencies for a sample of 200.

Test for independence of the row and column variables using a= .05

Compute the value of the  test statistic (to 2 decimals).

Suppose the heights of 18-year-old men are approximately normally distributed, with mean 72 inches and standard deviation 4 inches.

(a) What is the probability that an 18-year-old man selected at random is between 71 and 73 inches tall? (Round your answer to four decimal places.)


(b) If a random sample of thirty 18-year-old men is selected, what is the probability that the mean height x is between 71 and 73 inches? (Round your answer to four decimal places.)


(c) Compare your answers to parts (a) and (b). Is the probability in part (b) much higher? Why would you expect this?

The probability in part (b) is much higher because the standard deviation is smaller for the x distribution.

The probability in part (b) is much higher because the mean is larger for the x distribution.    

The probability in part (b) is much lower because the standard deviation is smaller for the x distribution.

The probability in part (b) is much higher because the mean is smaller for the x distribution.

The probability in part (b) is much higher because the standard deviation is larger for the x distribution.

Using the unit normal table, find the proportion under the standard normal curve that lies to the right of the following values. (Round your answers to four decimal places.)

(b) z = −1.05

(c) z = −2.40