Download Statistics Exam 1: Probability, Descriptive Statistics, and Correlation and more Exams Statistics in PDF only on Docsity! STAT 1200 Exam 1 Form A T. DeWees Name: Score: Honor Statement: By signing below you confirm that you have neither given nor received any unauthorized assistance on this exam. This includes any use of a graphing calculator beyond those uses specifically authorized by the Statistics Department and your instructor. Furthermore, you agree not to discuss this exam with anyone until the exam testing period is over. In addition, your calculator’s program memory and menus may be checked at any time and cleared by your instructor. Signature: Date: Show ALL work for ALL problems. 1. The Weight of Missouri Bulls taken in a 1998 study are normally distributed with a mean of 1555.3 lbs. with a standard deviation of 129.8 lbs. (a) (6 points) What is the probability that a bull will weigh more than 1623 lbs.? (b) (8 points) What is the probability that a bull will weight between 1468 lbs. and 1538 lbs.? 1 2. Use the following set of data to complete the problems on this page. The following data comes fro ACT scores taken by 10 high school students. 9, 26, 12, 18, 31, 15, 32, 24, 26, 21 (a) (3 points) Create a stem and leaf diagram for the data. (b) (9 points) Find the mean, median, and mode of the data. (c) (8 points) Find the variance, and standard deviation of the data. (d) (6 points) Determine if there are outliers. Show why or why not. (e) (5 points) Is the data Left Skewed, RIght Skewed, or Symmetric and why. 2 5. A Large appliance store has, in stock, 100 tv sets. 25 of the sets have small screens, 25 have medium screens, 25 have large screens, and 25 have huge screens. The store has the following lists available: List #1, all 100 sets; List # 2, the 25 small screens; List #3, the 25 medium screens; List #4, the 25 large screens; List #5, the 25 huge screens. For each of the following questions, identify the sampling scheme used to select the tvs. (a) ( 3 points ) Three tvs are randomly selected from each of List 2, List 3, List 4, and List 5 to produce a total sample of 12 tvs. (b) ( 3 points ) The owner writes the words small, medium, large, and huge each on one poker chip. He then randomly selects 2 of the poker chips and includes all 50 of the tvs in his sample. (c) ( 3 points ) Ten tvs are randomly selected from List 1 to produce a total sample of 10 tvs. (d) ( 3 points ) The owner selects the 1st and last tvs on each of List 2, List 3, List 4, and List 5 for a total of 8 sampled tvs. 5 6. (10 points) A study was conducted to compare smoking (You knew I had to pick a smoking question) cessation rates with the nicotine patches and placebos. Smokers were asked to quit using either a nicotine patch or a placebo patch. The data in the table below classifies the 240 participants in the study as to their treatment (patch or placebo) and whether or not they were smoking after eight weeks of treatment. Using the 5% significance level, does it appear that their is a relationship between quitting smoking and wearing a nicotine patch? Be sure to interpret your results. Still Smoking Not Smoking TOTAL Patch 64 56 120 Placebo 96 24 120 TOTAL 160 80 240 6
