5. Suppose X is the number of successes in a random sample of size n from a large population with a proportion of success p. What are the mean and the standard deviation of the sampling distribution of X in terms of n and p? The mean is np(l-pland the standard deviation is p(1-p) a. b. The mean is mPand the standard deviation is ap(1-p). C. The mean is p(1-pland the standard deviation is p. d. The mean is pand the standard deviation is p.

Recent studies have shown that about 16% of American adults fit the medical definition of being obese. A large medical clinic would like to estimate what percentage of their patients are obese, so they take a random sample of 400 patients and find that 52 are obese. Suppose that in truth, the same percentage holds for the patients of the medical clinic as for the general population, 16%.  Find the mean of the sampling distribution of p̂.

A population of values has a normal distribution with mean= 155.4 and standard deviation= 21.8. do you intend to draw a random sample of size n= 244.  A. Find P81, which is the value(X) separating the bottom 81% values from the top 19% values. B. Find P81, which is the sample mean separating the bottom 81% sample needs from the top 19% sample means.

Suppose a professor uses a normal distribution to assign grades in her math class. • She assigns an A to students scoring more than 1.9 standard deviations above the mean. • She assigns an F to students scoring more than 2.2 standard deviations below the mean. She assigns a B to students who Score between 1 and 1.9 standard deviations above the mean. • She assigns a D to students who Score between 1.2 and 2.2 standard deviations below the mean. • All other students get a C. Use the Cumulative Z-Score Table to answer the following questions. The Z-Score Table can be found below by selecting "Read". Write your answer as a percent using 2 decimal places. What percent of the class receives each grade assuming the scores are normally distributed? Hint % will recieve an A % will recieve a B % will recieve a C % will recieve a D % will recieve an F

In a poll conducted by the General Social Survey, 81% of respondents said that their jobs were sometimes or always stressful. Suppose a sample of 500 adults is takes and the proportion that say their jobs were sometimes or always stressful is recorded. Assuming np(1-p) > 10, what is the standard deviation of the sampling distribution of the sample proportion for this problem?

Suppose Jack and Diane are each attempting to use a simulation to describe the sampling distribution from a population that is skewed right with mean 60 and standard deviation 5. Jack obtains 1000 random samples of size n=5 from the​ population, finds the mean of the​ means, and determines the standard deviation of the means. Diane does the same​ simulation, but obtains 1000 random samples of size n=30 from the population   What do you expect the mean of Jack​'s distribution to​ be? What do you expect the mean of Diane​'s distribution to​ be?

3. Let X be the mean of a random sample of n = 25 from the distribution with a mean of 30 and a variance of 9. Find an approximated probability that the sample mean is between 29.8 and 30.6.

16. The distribution of the number of chocolate chips (x) in a cookie is shown in the following table. Find the mean and the variance of the number of chocolate chips in a cookie. 1 2 3 4 P(X = x) .01 .03 .05 .11 .13 6 7 8 P(X = x) .24 .22 .16 .05

The salaries of professional baseball players are heavily skewed right with a mean of $3.2 million and a standard deviation of $2 million. The salaries of professional football players are also heavily skewed right with a mean of $1.9 million and a standard deviation of $1.5 million. A random sample of 40 baseball players’ salaries and 35 football players’ salaries is selected. The mean salary is determined for both samples. Let  represent the difference in the mean salaries for baseball and football players. Which of the following represents the shape of the sampling distribution for ? skewed right since the populations are both right skewed skewed right since the differences in salaries cannot be negative approximately Normal since both sample sizes are greater than 30 approximately Normal since the sum of the sample sizes is greater than 30