1) The class sizes for Jims fall semester classes at XXX University are listed below. Class Ceramics Renaissance English Lit Ghost Hunting Statistics Time Period 8 9 AM 9 11 AM 1 2 PM 3 4 PM Class Sizes 22 14 28 14 Find the three measures of center. Which measure of center would you most like to use for the above data set? Why? 2) You are interested in finding the standard deviation of trees at XXX tree farm. You take a sample eight trees and record their heights below. What is the standard deviation of the trees that you samples? Tree Height: (in feet) 4.1, 6.2, 5.5, 7.1, 6.3. 5.9, 7.5, 6.7 The mean of the sampled trees is 6.3 3) Assume that you figure the real population standard deviation for all of the trees at XXX is 3.2. Construct a 95% confidence interval of all of the trees if a sample of 36 trees has a mean of 6.4 feet. 4) Please classify the following data as either qualitative or quantitative and lift its level of measurement. The waist sizes of mens jeans The most ordered ice cream flavor at Dairy Serf Total elevation at or below sea level The number of miles on your car Your friends favorite color 5) Two high schools are competing in a track meet. The next event is the one hundred meter dash. The coach of the Speedyville Cheetahs has asked you to construct an interval estimate of how much faster the opposing teams sprint unit is than the Cheetahssprinters. The Cheetahs coach tells you that five of his sprinters average 11.5 seconds in the 100 meter dash and that their times have a standard deviation of 0.15 seconds. He says that his runners times are normally distributed. The Cheetahs coach also scouted the other team, the Fleettown Rockets. He was able to observe six of their runners. The Rockets sprinters had an average time of 11.35 seconds with a standard deviation of 0.2 seconds. The Cheetahs coach believes that the Rockets times are normally distributed as well. Construct a 95% confidence interval the Coach to compare the means of the two teams sprint units! 6) You are picking up walnuts from a tree in a nearby park. Suddenly you become interested in estimating the mean weight of all of the walnuts in that park. Unfortunately you have only been able to find seven walnuts so far. Can you use the Central Limit Theorem to aid in your estimations? Why or why not? 7) Assume that the weights of coconuts are normally distributed with a mean weight of 17.6 pounds and a standard deviation of 1.2 pounds. If you are in Cabo Rico on spring break with your friends and a coconut falls on your head, what is the likelihood that the coconut weighs less than 16 pounds? 8) You are preparing to do an ANOVA test. You have the following sample sizes and sample means: Sample Size 15 20 14 16 Sample Mean 64 68 59 63 What is the Grand Mean for this data? 9) Please draw a bar graph for the following data. Remember to include all necessary elements of a graph! Favorite Ice Cream Flavor Chocolate Frequency 5 Vanilla Strawberry Other 8 2 4 You may use the next page of the test. 10) What z-score corresponds to the 85th percentile in a normal distribution? 11) Karen took the ACT yesterday. She found out that if the scores were ranked in order from highest to lowest, she was number twenty-two out of 265 students. What percentile did Karen score in? 12) You are a new manager at a Lowbucks coffee shop. Your workers are already complaining! They want you to hire more help. They claim that they are having to make at least 200 cups of coffee an hour. You doubt that, so you take a sample over a few hours and find that over a four hour period one Friday afternoon, the workers averaged 191 cups of coffee per hour, with a standard deviation of 6 cups. Using a significance level of 0.05, perform a hypothesis test to see if the workers are right, and you need to hire more help. Write your hypotheses, calculate your test statistic and decide whether or not to reject your null. 13) When working with hypothesis tests, we always choose a level of significance? What is the level of significance and why do we want to be careful when selecting a level of significance? 14) An ANOVA test is a type of hypothesis test. What does an ANOVA test look for, and what are the null and alternative hypotheses for an ANOVA test? 15) Draw a box and whisker plot off of the following five number summary (remember to draw a number line): 4, 6, 10, 35, 50 16) What is the interquartile range of the five number summary in question 15?
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