Week_One_Individual_Assigment__Descriptive_Statistics_and_Probability_Distributions_Problem_Sets

Week One Individual Assigment: Descriptive Statistics and Probability Distributions Problem Sets QNT/561 Applied Business Research and Statistic Individual Assignment: Descriptive Statistics and Probability Distributions Problem Sets * Prepare responses to the following exercises from the text: * Exercises 80, 82, and 87 (Ch. 3) * Exercises 34, 36, and 38 (Ch. 5) * Exercises 45 and 62 (Ch. 6) * Exercises 42 and 45 (Ch. 7) Exercises 80 (Ch. 3) Creek Ratz is a very popular restaurant located along the coast of northern Florida. They serve a variety of steak and seafood dinners. During the summer beach season, they do not take reservations or accept “call ahead” seating. Management of the restaurant is concerned with the time a patron must wait before being seated for dinner. Listed below is the wait time, in minutes, for the 25 tables seated last Saturday night. 28, 39, 23, 67, 37, 28, 56, 40, 28, 50, 51, 45, 44, 65, 61, 27, 24, 61, 34, 44, 64, 25, 24, 27, 29 a. Explain why the times are a population. - This is a population because we are considering all the tables seated last Saturday night. b. Find the mean and median of the times. - Median: 23,24,24,25,27,27,28,28,28,29,34,37,39,40,44,44,45,50,51,56,61,61,64,65,67 * Mean: Interpretation: The typical time a patron must wait before being seated is 40.84 minutes. ∑ X 1,021 µ = ______ = ______ = 40.84 N 25 c. Find the range and the standard deviation of the times. - Range: Range = Largest Value – Smallest Value = 67 - 23 = 44 * Standard Deviation: Exercises 82 (Ch. 3) The following frequency distribution reports the electricity cost for a sample of 50 twobedroom apartments in Albuquerque, New Mexico during the month of May last year. Electricity Cost Frequency | $ 80 up to $100 3 100 up to 120 8 120 up to 140 12 140 up to 160 16 160 up to 180 7 180 up to 200 4 Total 50 | a. Estimate the mean cost Frequency | X- | (X-)2 | 3 8 12 16 7 4_ 50 | -5.33 -.33 3.70 7.70 -1.33 4.33 | 1.00 .1150.7059.00 1.8018.70_131.31 | * = Xn = 3+8+12+16+7+46 = 506 * = 8.33 Mean Cost = 8.332 b. Estimate the standard deviation. X-2n-1= 131.316-1= 131.315= 131.315= 26.3=5.12 c. Use the Empirical Rule to estimate the proportion of costs within two standard deviations of the mean. What are these limits' Exercise 87 (Ch. 3) Refer to the Real Estate data, which reports information on homes sold in the Denver, Colorado, area last year. a. Select the variable selling price. 1. Find the mean, median, and the standard deviation. - Mean 221.10 - Median 213.60 - Standard deviation 47.11 2. Write a brief summary of the distribution of selling prices. - Symmetric 220,000 dollars. b. Select the variable referring to the area of the home in square feet. 1. Find the mean, median, and the standard deviation. - Mean 2,223.8 - Median 2,200 - Standard deviation 248.7 2. Write a brief summary of the distribution of the area of homes. - Symmetric 2,200 feets Exercise 42 (Ch. 7) The accounting department at Weston Materials, Inc., a national manufacturer of unattached garages, reports that it takes two construction workers a mean of 32 hours and a standard deviation of 2 hours to erect the Red Barn model. Assume the assembly times follow the normal distribution. a. Determine the z values for 29 and 34 hours. .4332 .3413 .1587 29 32 34 -1.5 1 Scale in z z=29-322=29-322=-32= -1.5 z=34-322=34-322=22= 1