In a school with 400 students, 150 students are currently taking advanced placement (AP) classes, and 40 students are seniors taking advanced placement classes. There are 100 seniors in all.

Use the given information to create a two-way frequency table. Include the categories Seniors and Not Seniors, and AP Classes and No AP Classes.

What are the steps of the nursing process?

Andersen Windows makes windows for use in homes and commercial buildings. The standards for glass thickness call for the glass to average 0.375 inch with a standard deviation equal to 0.050 inch. Suppose a random sample of n=50 windows yields a sample mean of 0.392 inch.

a. What is the probability of $\bar{x} \geq 0.392$ if the windows meet the standards?

b. Based on your answer to part a, what would you conclude about the population of windows? Is it meeting the standards?

A decision maker is interested in estimating a population proportion. A sample of size n=150 yields 115 successes. Based on these sample data, construct a 90% confidence interval estimate for the true population proportion.

A decision maker is interested in estimating the mean of a population based on a random sample. She wants the confidence level to be 90% and the margin of error to be $\pm$ 0.30. She does not know what the population standard deviation is, so she has selected the following pilot sample:

$$\begin{array}{rrrrr} \hline 8.80 & 4.89 & 10.98 & 15.11 & 14.79 \\ 16.93 & 1.27 & 9.06 & 14.38 & 5.65 \\ 7.24 & 3.24 & 2.61 & 6.09 & 6.91 \\ \hline \end{array}$$

Based on this pilot sample, how many more items must be sampled so that the decision maker can make the desired confidence interval estimate?

Given a population in which the probability of success is p=0.20, if a sample of 500 items is taken, then

a. Calculate the probability the proportion of successes in the sample will be between 0.18 and 0.23.

b. Calculate the probability the proportion of successes in the sample will be between 0.18 and 0.23 if the sample size is 200.

A phone service provider offers two international plans.

A normally distributed population has a mean of 500 and a standard deviation of 60.

a. Determine the probability that a random sample of size 16 selected from this population will have a sample mean less than 475.

b. Determine the probability that a random sample of size 25 selected from the population will have a sample mean greater than or equal to 515.

Given a population in which the proportion of items with a desired attribute is p=0.25, if a sample of 400 is taken,

a. What is the standard deviation of the sampling distribution of $\bar{p}$?

b. What is the probability the proportion of successes in the sample will be greater than 0.22?

Identify the (a) sample and (b) population. Also, decide whether the sample is possible to be representative of the population.

USA Today Survey The newspaper USA Today published a health survey, and some readers completed the survey and returned it.

According to a USA Today "Snapshot," 3% of Americans surveyed lie frequently. You conduct a survey of 500 college students and find that 20 of them lie frequently.

Does this result contradict the USA Today "Snapshot"? Explain.

The dishonest mechanic ______ automobiles and then charged customers for the repairs.

The J R Simplot Company is one of the world's largest privately held agricultural companies in North America. One of its major products is french fries that are sold primarily on the commercial market to customers such as McDonald's and Burger King. French fries have numerous quality attributes that are important to customers. One of these is called "dark ends," which are the dark-colored ends that can result when the fries are cooked. Suppose a major customer will accept no more than 0.06 of the fries having dark ends.

The customer called the Simplot Company saying that a recent random sample of 300 fries was tested from a shipment and 27 fries had dark ends. Assuming that the population does meet the 0.06 standard, what is the probability of getting a sample of 300 with 27 or more dark ends? Comment on this result.

Most major airlines allow passengers to carry one luggage item (of a certain maximum size) and one personal item onto the plane. However, suppose the more carry-on baggage passengers have, the longer it takes to unload and load passengers. One regional airline is considering changing its policy to allow only one carry-on item per passenger. Before doing so, it decided to collect some data. Specifically, a random sample of 1,000 passengers was selected. The passengers were observed, and the number of bags carried on the plane was noted. Out of the 1,000 passengers, 345 had two carry-on items.

a. Based on this sample, develop and interpret a 95% confidence interval estimate for the proportion of the traveling population that would have been affected if the one-bag limit had been in effect. Discuss your result.

b. The domestic version of Boeing's 747 has a capacity for 568 passengers. Determine an interval estimate of the number of passengers that you would expect to carry more than one piece of luggage on the plane. Assume the plane is at its passenger capacity.

c. Suppose the airline also noted whether each passenger was male or female. Out of the 1,000 passengers observed, 690 were males. Of this group, 280 had more than one bag. Using these data, obtain and interpret a 95% confidence interval estimate for the proportion of male passengers in the population who would have been affected by the one-bag limit. Discuss.

d. Suppose the airline decides to conduct a survey of its customers to determine their opinion of the proposed one-bag limit. Airline managers expect that only about 15% will approve of the proposal. Based on this assumption, what size sample should the airline take if it wants to develop a 95% confidence interval estimate for the population proportion who will approve with a margin of error of $\pm$ 0.02?