Mock_Final_Exam1

Improve Life University of Guelph Statistics for Business Decisions Final Mock Exam Dr. Clémonell Bilayi-Biakana. Student Information: • First Name : • Last Name : • Student Number : • Section : Instructions: 1. You have 120 minutes to complete this final examination. This is an in-person proctored exam . 2. Out of 6 equally weighted proposed exercises on this final exam, you must solve only 4 . You will not get extra marks for solving all 6. If you do not solve only 4 of the 6 proposed exercises, the TA will randomly choose 4 out of the 6 you solved. Each proposed exercise is worth 10 points and your answers need to be justified to get full marks . 3. Your name, section, and student number should be written on your exam paper as they appear on Courselink . 4. Only basic scientific calculators are allowed. Programmable calculators are not. The final exam comes with statistical charts ( z and t -charts). You don’t have to print them out. 5. You are allowed to use the formula sheet posted on Courselink during this test. It must exclusively contain formulas . 6. You are not allowed to communicate with your peers during this exam. Do not look at their work either. Any question regarding the midterm should directly be asked to the instructor not to the TAs. They are not aware of the exam content . 7. Smartphones have to be turned off during exam period. Personal belong- ings such as bags should be put on the stage. 1

Improve Life Exercise 1: The marketing director of a large department store wants to estimate the average number of customers who enter the store every five minutes. She randomly selects five-minute intervals and counts the number of arrivals at the store. She obtains the figures 58, 32, 41, 47, 56, 80, 45, 29, 32, and 78. The analyst assumes the number of arrivals is normally distributed. Using these data, the analyst computes a 95% confidence interval to estimate the mean value for all five-minute intervals. What interval values does she get? Exercise 2: 1. The highway department wants to estimate the proportion of vehicles on Ontario’s Highway 401 between the hours of midnight and 5 A.M. that are 18-wheel tractor trailers. The estimate will be used to determine highway repair and construction considerations and in highway patrol planning. Suppose analysts for the highway department counted vehicles at different locations on the highway for several nights during this time period. Of the 3,481 vehicles counted, 927 were 18-wheelers. Construct a 99% confidence interval for the proportion of vehicles on Highway 401 during this time period that are 18-wheelers. 2. Suppose 80% vehicles on Ontario’s Highway 401 between the hours of midnight and 5 A.M. that are 18-wheel tractor trailers. What is the prob- ability of taking a sample of size 150 from vehicles on Ontario’s Highway 401 between the hours of midnight and 5 A.M. and finding that between 68% and 81% are 18-wheelers? Exercise 3: According to Canadian Radio-television and Telecommunications Commission, the number of hours of TV viewing among adults is uniformly distributed be- tween a and 27 hours per week. Its standard deviation is 6.7 hours. 1. What is the minimum number of hours per week, a , that Canadian adults spend watching TV? What is the probability that a Canadian spends between 7 and 12 hours watching television? 2. A random sample of 42 Canadian adult households is taken. What is the probability that the total number of hours of TV viewing among adults is less than 523 ? Exercise 4: At Canon Food Corporation, it used to take an average of 90 minutes for new workers to learn a food processing job. Recently the company installed a new food processing machine. The supervisor at the company wants to find if the mean time taken by new workers to learn the food processing procedure on 2