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#1 Typing speeds (in words per minute) of 20 applicants for a secretarial position are as follows: 55 44 63 47 28 83 46 55 53 72 54 83 70 61 36 46 50 35 56 43 Complete this grouped data table using 20 as the first cutpoint and class width 10: Typing Speed (Words per Minute) Frequency Relative Frequency Midpoint #2 Mailing costs (in dollars) for 14 packages are as follows: 9.12 12.60 8.75 7.90 15.08 8.20 14.66 6.50 6.82 5.33 8.47 13.20 6.79 8.82 Draw a frequency histogram for this data, using 4 as the first cutpoint and class width 2. Put appropriate titles on the axes. #3 Let X = the number of successes in n = 7 trials X P(X = x) in a binomial experiment in which the 0 0.0044 success probability is P(s) = 0.54. 1 Fill in the three missing probabilities in the 2 table (to 4 decimal places of accuracy). 3 4 0.2897 5 0.2040 6 0.0798 7 0.0134 #4 As reported in Scott M. Berry's article, \Drive for Show and Putt for Dough", the mean distance for tee shots on the men's 1999 PGA tour is = 272.2 yards with standard deviation = 8.12 yards. Assume that the tee-shot distances are normally distributed. What is the probability that a tee-shot goes between 257 and 287 yards? Give your answer to 4 decimal places. #5 Let be the mean systolic blood pressure of men aged 18 to 29. Determine a 90% confidence interval for , based on a sample of 36 men aged 18 to 29 in which the sample mean blood pressure is 120 mmHg. (Assume = 10.2 mmHg.) Give your answer accurate to 3 decimal places. #6 Payment for a truckload of Florida oranges depends on the amount of sugar in the oranges. How many oranges should be tested to estimate mean sugar concentration within a margin of error of 0.55 grams per liter at 90% confidence level? (Assume = 2.6 grams per liter.) #7 Consider the hypothesis test { Suppose critical values of z are 2 and – 2. Suppose (a) What is the appropriate decision? (b) For a true , is the decision a Type I error? (c) For a false is the decision a Type II error? #8 Relative frequencies are given for all vehicle registrations: Vehicle Size Compact Mid Full Commercial But a sample of 300 accident reports is summarized as follows: p 0.21 0.46 0.31 0.02 Vehicle Size Compact Mid Full Commercial Observed Frequency 51 124 115 10 (a) The Goodness-of-Fit Test is used in this problem. In other words, hypothesis that accidents occur in the given population proportions. Show step by step the calculation of (b) Make a decision (to reject Justify your decision. . or not) at significance level = 0.01. is the #10 Parents of 120 children were asked whether they played “I Spy” games with their children. The following data were obtained: Frequency of Games (a) In the Social Class NEVER SOMETIMES OFTEN MIDDLE 10 13 25 WORKING 14 23 35 independence test the hypothesis is that social class and frequency of games are not associated. Show step by step the calculation of (b) Make a decision (to reject Justify your decision. or not) at significance level = 0.01. .