# Business statistics Statistics Question

SAD 221 – Final Exam – Spring 2021 Record all answers on the separate answer sheet provided. Upload the Ans Sheet file (or a picture) to Black Board by Tuesday, May 18. Problem #1 Thirty students in the School of Business were asked for the first letter of their last name . The following represents their responses (A- Anderson, J- Johnson, S- Sawyer, and W – Williams). A W J J S A J J S A A A J S J A W W W J W J A J S J A A A J Refer to the observations above and complete the table below by placing answers on your answer sheet: Major J A W S Total Frequency Relative Frequency Percent Frequency 30 1.0 100% Cumulative Frequency 30 In the space provided on your answer sheet, draw a Pie Chart using the percent frequency values above.

Write in the data label value inside each piece of pie. Problem #2 You are given the following data on the ages of employees at a company. 66 52 41 42 32 44 53 64 28 36 35 60 45 42 28 36 18 27 32 57 Construct a stem-and-leaf display in the space provided on your answer sheet. Problem #3 Determine the weighted mean (Semester GPA) for the following student: Points are earned based upon the following scale: A 4.0, B 3.0, C 2.0 and D 1.0 Business Math Accounting Computer Applications Composition Psychology Keyboarding Semester Grade B C A B B D Credits per Course 3 3 1 3 3 1 Problem #4 – Complete the question below: assignments apply: P(E1)= .10, P(E2) = .05, P(E3) = .25, P(E4) = .05, P(E5) = .15, P(E6) = .20, P(E7) = .20 A = [E1, E4, E6] B = [E2, E4, E7] C= [E2, E3, E5, E7] e. Complement of B and the Probability of the Complement of B Transfer answers on the ANS Sheet provided for credit

4a. ____________ _____________ _______________ (2 decimal places)

4b. _________________________(outcomes) _____________ (2 decimal places)

4c._________________________ (outcomes) _______________ (2 decimal places)

4d. __________________________

4e. ________________________ (outcomes) __________________ (2 decimal places) For

Questions # 5: Standard deviation of the population is known and the z value for the confidence levels are as follows: 90% Confidence Level 95% Confidence Level 99% Confidence Level z value = 1.645 z value = 1.960 z value = 2.576 Problem #5 A sample random sample of 49 items resulted in a sample mean of 120. The population standard deviation equal 16. a. Compute a 99% confidence interval for the population mean. b. Compute a 90% confidence interval for the population mean. For

Questions # 6: Standard deviation of the population is unknown – use the t-table provided to compute the margin of error needed for the confidence interval. Problem #6 – 20 employees’ required training days for mastery of a piece of equipment are listed below: 140 340 330 130 440 300 330 250 430 230 390 230 400 390 340 550 240 500 450 230 a. b. c. d. What is the sample mean? What is the sample standard deviation? (Hint: easier to use Excel) What is the degrees of freedom? What is the margin of error at a 95% confidence level? BSAD 221 – FINAL EXAM – Answer Sheet Name: Problem #1 Major J A W S Total (2 decimals) Frequency Relative Frequency Percent Frequency Cumulative Frequency 30 30 1 Problem #1 – Draw Pie Chart in the Box: Problem #2: Stem and Leaf Display 100% Problem #3 Student’s GPA 2 decimals Problem #4 (2 deicimals for probabilities) 4a. P(A) 4a P(B) 4a P( C) 4b AuB Outcomes 4b P(AuB) 4c AnB Outcomes 4c P(AnB) 4d Yes or No? 4e Bc Outcomes 4e P(Bc ) 5a. (3 decimals) 5 b. (3 decimals) 6a. (0 decimals) 6b. (3 decimals) 6c. (0 decimals) 6d. (3 decimals)