Extending Concepts Interchanging x and y In Exercises 30 and 31, do the following. (a) Find the equation of the regression line for the given data, letting Row 1 represent the x-values and Row 2 the y-values. Sketch a scatter plot of the data and draw the regression line. SECTION 9.2 LINEAR REGRESSION 521 (b) Find the equation of the regression line for the given data, letting Row 2 represent the x-values and Row 1 the y-values. Sketch a scatter plot of the data and draw the regression line. (c) What effect does switching the explanatory and response variables have on the regression line? 30. Row 1 16 25 39 45 49 64 70 Row 2 109 122 143 132 199 185 199 31. Row 1 0 1 2 3 3 5 5567 Row 2 96 85 82 74 95 68 76 84 58 65 2. The table lists the number of U.S. mainland hurricane strikes (from 1901 to 2004) for various intensities according to the Saffir-Simpson Hurricane Scale. (Source: National Hurricane Center) ni tlues Jon bib ledt eelys TA 01 mobn ex way bas idgin or is bebivornosti or Jost at 1996nam ov li smirmob of Number of Intensity hurricanes 1 70 2 se that 41 You 3. 49 4 5 13 3 TA olaz of Tong in the JoW woll I (sk by (A)s d with (a) Construct a probability distribution of the data. algo ton (b) Graph the discrete probability distribution using a probability histogram. (c) Find the mean, variance, and standard deviation of the probability distribution and interpret the results. (d) Find the probability that a hurricane selected at random for further study has an intensity of at least four. 20-00 Graphical Analysis In Exercises 17 and 18, use the frequency histogram to (a) determine the number of classes. (b) estimate the frequency of the class with the least frequency. (c) estimate the frequency of the class with the greatest frequency. (d) determine the class width. 17. Frequency Employee Salary 18. Tree Height 900 300 750 250 200 150 Frequency 600 450 100 50 300 150 24.5 34.5 44.5 54.5- 64.5- 74.5- 84.5 Salary (in thousands of dollars) zpl 18 23 28 33 38 43 48 Height (in inches) Graphical Analysis In Exercises 19 and 20, use the ogive to approximate (a) the number in the sample. (b) the location of the greatest increase in frequency. Male Beagl Male Beagles 20. Adult Female Ages 20-29 19. 55 Cumulative frequency 50 45 40 35 30 25 20 15 10 5 + 18.5 21.5 24.5 27.5 30.5 33.5 Weight (in pounds) 15 10 58443222E05 Cumulative frequency 58 60 62 64 66 68 70 72 74 Height (in inches) 21. Use the ogive in Exercise 19 to approximate (a) the cumulative frequency for a weight of 24.5 pounds. (b) the weight for which the cumulative frequency is 45. 22. Use the ogive in Exercise 20 to approximate (a) the cumulative frequency for a height of 70 inches. (b) the height for which the cumulative frequency is 25. that otball teamsS 11 12 1 10 2 (4/6/23 THURSDAY 9 8 4 765 PG 50 17-22 PG 235 #2- No o PG 357 5 PG 521 # 31 OR 52 3 5. In a survey of 1037 adults from the United States age 65 and over, 643 were concerned about getting the flu. (Source: Harvard School for Public Health) (a) Find a point estimate for the population proportion p of those concerned about getting the flu. (b) Construct a 90% confidence interval for the population proportion. (c) Find the minimum sample size needed to estimate the population proportion at the 99% confidence level in order to ensure that the estimate is accurate within 4% of the population proportion.