In a study of government financial aid for college​ students, it becomes necessary to estimate the percentage of​ full-time college students who earn a​ bachelor's degree in four years or less. Find the sample size needed to estimate that percentage. Use a 0.04 margin of error and use a confidence level of 90​%. Complete parts​ (a) through​ (c) below.

a. Assume that nothing is known about the percentage to be estimated.

n=________(Round up to the nearest​ integer.)

b. Assume prior studies have shown that about 60​% of​ full-time students earn​ bachelor's degrees in four years or less.

c. Does the added knowledge in part​ (b) have much of an effect on the sample​ size?

A.

​No, using the additional survey information from part​ (b) does not change the sample size.

B.

​Yes, using the additional survey information from part​ (b) only slightly increases the sample size.

C.

​No, using the additional survey information from part​ (b) only slightly reduces the sample size.

D.

​Yes, using the additional survey information from part​ (b) dramatically reduces the sample size.

a) A manager at the Kemboja Car Sales and Services Enterprise wishes to estimate the number of days it takes for his car dealer to sell a local made car model. A random sample of 50 cars was selected and the mean number of days his car dealer is able to sell a local made car is 50 days. Assume the population standard deviation is 6 days.

i) Find the best point estimate of the population mean. Find the standard error of the

mean.

ii) Calculate the 99% confidence interval of the population mean number of days a car

dealer is able to sell a local made car.

b) As an aid for improving students’ study habit, 6 students were randomly selected to attend a seminar on the importance of education in life. The table shows the number of hours each student studied per week before and after the seminar. At the 95% confidence interval, did attending seminar increase the mean number of hours the students studied per week?

Before 12 15 18 10 13 5 After 17 20 21 15 22 7

Given Σd = - 29; Σd2 = 169

The number of students taking the SAT has risen to an all-time high of more than 1.5 million The number of times the SAT was taken and the number of students are as follows.

a. Let x be a random variable indicating the number of times a student takes the SAT. Show the probability distribution for this random variable. Round your answers to four decimal places.

b. What is the probability that a student takes the SAT more than one time? Round your answer to four decimal places.

c. What is the probability that a student takes the SAT three or more times? Round your answer to four decimal places.

d. What is the expected value of the number of times the SAT is taken? Round your interim calculations and final answer to four decimal places.

e. What is the variance and standard deviation for the number of times the SAT is taken? Round your interim calculations and final answer to four decimal places.

Franklin Training Services (FTS) provides instruction on the use of computer software for the employees of its corporate clients. It offers courses in the clients’ offices on the clients’ equipment. The only major expense FTS incurs is instructor salaries; it pays instructors $6,000 per course taught. FTS recently agreed to offer a course of instruction to the employees of Novak Incorporated at a price of $700 per student. Novak estimated that 20 students would attend the course.

Base your answers on the preceding information.

FTS sells a workbook with printed material unique to each course to each student who attends the course. Any workbooks that are not sold must be destroyed. Prior to the first class, FTS printed 20 copies of the books based on the client’s estimate of the number of people who would attend the course. Each workbook costs $30 and is sold to course participants for $50. This cost includes a royalty fee paid to the author and the cost of duplication.

Calculate the workbook cost in total and per student, assuming that 18, 20, or 22 students attempt to attend the course.

Classify the cost of workbooks as fixed or variable relative to the number of students attending the course.

The owner of a small company asked a CPA to conduct an audit of the company's records. The owner of the company told the CPA that the audit was to be completed in time to submit audited financial statements to a bank as part of a loan application. The CPA immediately accepted the engagement and agreed to provide an auditor's report within three weeks. The owner agreed to pay the CPA a fixed fee plus a bonus if the load was granted.

The CPA hired two accounting students to conduct the audit and spent several hours telling them exactly what to do. The CPA told the students not to spend time reviewing the internal controls but instead to concentrate on proving the mathematical accuracy of the ledger accounts and summarizing the data in the accounting records that supported the company's financial statements. The students followed the CPA's instructions and after two weeks gave the CPA the financial statements which did not include any footnotes. The CPA reviewed the statements and prepared an unmodified auditor's report. The report did not refer to GAAP or to the consistent application of GAAP.

Briefly describe at least three principles underlying AICPA auditing standards and indicate how the actions of the CPA resulted in a failure to comply with each principle.

In a study of government financial aid for college​ students, it becomes necessary to estimate the percentage of​ full-time college students who earn a​ bachelor's degree in four years or less. Find the sample size needed to estimate that percentage. Use a 0.03 margin of error and use a confidence level of 99​%.

Complete parts​ (a) through​ (c) below.

a. Assume that nothing is known about the percentage to be estimated.

n = ?

​(Round up to the nearest​ integer.)

b. Assume prior studies have shown that about 60% of​ full-time students earn​ bachelor's degrees in four years or less.

n =?

​(Round up to the nearest​ integer.)

c. Does the added knowledge in part​ (b) have much of an effect on the sample​ size?

A.

​Yes, using the additional survey information from part​ (b) dramatically reduces the sample size.

B.

​Yes, using the additional survey information from part​ (b) only slightly increases the sample size.

C.

​No, using the additional survey information from part​ (b) only slightly reduces the sample size.

D.

​No, using the additional survey information from part​ (b) does not change the sample size.

Q1 What happens to the sample mean and standard error as N increases?

Q2 What are the three different t-tests and describe what is different between them

a. What are the assumptions for each test?

Q3 How is the z-score distinct from the t-statistic?

Q4 I want to know if students in my Math class of 27 students are doing as well as another Math class taught by a different teacher, their class has 23 students. What t-test should I use to determine if there is a statistical significant difference between the two classes?

My class has a mean of 87 while the other class has 92. The standard error of the difference is .55

1. State the null and alternate hypothesis
2. Determine the tstatistic and df
3. Using the ttable, what is the critical region?
4. Is there a statistical significant difference?
5. What is the effect size?

Q5 What are 3 key differences between a one-tailed hypothesis versus a two-tailed hypothesis?

Q6 What is a Type 1 error?

Q7 What is a Type 2 error?

Q8 Name one way to increase power and one way to decrease power

You have developed your own questionnaire to assess emotional intelligence in adults. You want to compare a group of professors to a group of undergraduate students. You randomly select 5 professors and 5 students to answer the questions on your questionnaire. You want to determine whether the two groups are different on emotional intelligence. Below are the data you collected, with higher scores showing more emotional intelligence on your questionnaire.

What are your null and alternative/research hypotheses for these data? What is the degrees of freedom (df) and your critical (cutoff) t score value for the test (using .05, two-tailed criterion values)? (3 points)

Compute the standard deviation of the distribution of the difference between group means (or the S_difference) from the pooled variances and then use that value to perform an independent-sample t test on these data and report the t-statistic. (4 points)

Using the findings from the t test, what can you conclude? Report the results following APA format for reporting the t-test. (3 points)

Confidence Interval 1

All of the questions with the header "Confidence Interval 1" are based on the data in this problem.

A researcher at the Annenberg School of Communication is interested in studying the use of smartphones among young adults. She wants to know the average amount of time that college students in the United States hold a smartphone in their hand each day. The researcher obtains data for one day from a random sample of 25 college students (who own smartphones). She installs an app that registers whenever the smartphone is being held and the screen is on. The sample mean is 230 minutes, with a standard deviation of 11 minutes.

What is the 95% confidence interval for average daily time a smartphone is used among college students?

Please show all work for this question on your own sheet of paper. Take your time and organize it neatly with plenty of space. You will upload your work at the end. For some questions, just enter your answer in Canvas.

1. What value of t is used in the confidence interval?

2. What is the standard error?

3. What is the lower bound of the confidence interval?   

4. What is the upper bound of the confidence interval?