Suppose a random sample of n = 16 communities in western Kansas gave the following information...

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Suppose a random sample of n = 16 communities in western Kansas gave the following information for people under 25 years of age. X: Rate of hay fever per 1,000 population for people under 25 99 89 121 127 93 124 111 94 126 96 124 116 98 121 128 89 Suppose a random sample of n = 14 regions in western Kansas gave the following information for people over 50 years old. X2: Rate of hay fever per 1,000 population for people over 50 94 109 100 96 113 87 111 80 116 99 88 112 84 97 USE SALT (a) Use a calculator to calculate X1, S1, X2, and S2. (Round your answers to four decimal places.) (b) Assume that the hay fever rate in each age group has an approximately normal distribution. Do the data indicate that the age group over 50 has a lower rate of hay fever? Use a = 0.05. (i) What is the level of significance? (ii) What sampling distribution will you use? What assumptions are you making? It follows the Student's t sampling distribution. We assume that both population distributions are approximately normal with known standard deviations. It follows the Student's t sampling distribution. We assume that both population distributions are approximately normal with unknown standard deviations. It follows the standard normal sampling distribution. We assume that both population distributions are approximately normal with known standard deviations. It follows the standard normal sampling distribution. We assume that both population distributions are approximately normal with unknown standard deviations. Use the sample test statistic to find the corresponding z or t value as appropriate. (Test the difference - . Round your answer to two decimal places.) (iii) Find (or estimate) the P-value. webassign.net/web/Student/Assignment-Responses/last?dep=33455659#Q17 U Relaunch to update ! Career School 17. [-/2 Points] DETAILS MY NOTES BBUNDERSTAT13 9.2.016.S. ASK YOUR TEACHER PRACTICE ANOTHER It is thought that basketball teams that make too many fouls in a game tend to lose the game even if they otherwise play well. Let x be the number of fouls that were more than (l.e., over and above) the number of fouls made by the opposing team. Let y be the percentage of times the team with the larger number of fouls wins the game. 1 456 y 49 43 33 26 In USE SALT Complete parts. (a) through (e) after verifying that Ex = 16, 2y = 151, Ex = 78, y = 6,015, xy = 542, and r = -0.9340. (a) Draw a scatter diagram displaying the data. 6 SI 5 y (percentage) 3. 4 2 50 esc F1 2 F2 30 30 35 x (fouls) y (percentage) 2 6 5 1 40 45 30 35 40 45 x (fouls) APR 19 tv 50 80 F3 000 000 F4 F5 @ # 3 4 $ % 5 F6 & 7 ZOOM A G P W NEW 87 DI FB FB F10 00 9 0 B Profiles Tab Window Help X Math 1025 Wk 16: Prac HW CI x M Math 1025 Wk 15: Practice Qu x Cengage Learning webassign.net/web/Student/Assignment-Responses/last?dep=33455659#Q17 C Career School 50 45 y (percentage) 35 35 40 40 (b) Find x. X = 30 x (fouls) y (percentage) 501. 45 40 35 30 + x (fouls) 25 1 2 3 4 5 6 25 1 2 3 4 5 6 x (fouls) x (fouls) Find y (in %). % i Find the equation of the least-squares line = a + bx. (Round your numerical values to four decimal places.) = (c) Graph the least-squares line. Be sure to plot the point (x, y) as a point on the line. APR 1 19 tv 200M AG X P W NEW U Fri Apr 19 6: Relaunch to upda School sponses/last?dep=33455659#Q17 (c) Graph the least-squares line. Be sure to plot the point (x, y) as a point on the line. 50 45 y (percentage) 35 35 40 y (percentage) 30 y (percentage) 5 4 3 2 25 1 1 2 3 4 5 6 30 35 x (fouls) 6 5 3 2 1 A APR 19 1 tv y (percentage) 50+ 45 40 35 30 25 x (fouls) 40 45 zoom AG GO X W NEW U Rela 2 = 6 5 y (percentage) 3 4 2 X (100s) 50 45 30 y (percentage) 35 35 40 X (IOUIS) 1 25 30 35 40 45 1 2 3 4 5 6 x (fouls) x (fouls) (d) Find the value of the coefficient of determination 2. (Round your answer to four decimal places.) % What percentage of the variation in y can be explained by the corresponding variation in x and the least-squares line? (Round your answer to two decimal places.) What percentage is unexplained? (Round your answer to two decimal places.) % (e) If a team had x = 3 fouls over and above the opposing team, what does the least-squares equation forecast for y (in %)? (Round your answer to two decimal places.) % O APR 1 A 19 Suppose a random sample of n = 16 communities in western Kansas gave the following information for people under 25 years of age. X: Rate of hay fever per 1,000 population for people under 25 99 89 121 127 93 124 111 94 126 96 124 116 98 121 128 89 Suppose a random sample of n = 14 regions in western Kansas gave the following information for people over 50 years old. X2: Rate of hay fever per 1,000 population for people over 50 94 109 100 96 113 87 111 80 116 99 88 112 84 97 USE SALT (a) Use a calculator to calculate X1, S1, X2, and S2. (Round your answers to four decimal places.) (b) Assume that the hay fever rate in each age group has an approximately normal distribution. Do the data indicate that the age group over 50 has a lower rate of hay fever? Use a = 0.05. (i) What is the level of significance? (ii) What sampling distribution will you use? What assumptions are you making? It follows the Student's t sampling distribution. We assume that both population distributions are approximately normal with known standard deviations. It follows the Student's t sampling distribution. We assume that both population distributions are approximately normal with unknown standard deviations. It follows the standard normal sampling distribution. We assume that both population distributions are approximately normal with known standard deviations. It follows the standard normal sampling distribution. We assume that both population distributions are approximately normal with unknown standard deviations. Use the sample test statistic to find the corresponding z or t value as appropriate. (Test the difference - . Round your answer to two decimal places.) (iii) Find (or estimate) the P-value. webassign.net/web/Student/Assignment-Responses/last?dep=33455659#Q17 U Relaunch to update ! Career School 17. [-/2 Points] DETAILS MY NOTES BBUNDERSTAT13 9.2.016.S. ASK YOUR TEACHER PRACTICE ANOTHER It is thought that basketball teams that make too many fouls in a game tend to lose the game even if they otherwise play well. Let x be the number of fouls that were more than (l.e., over and above) the number of fouls made by the opposing team. Let y be the percentage of times the team with the larger number of fouls wins the game. 1 456 y 49 43 33 26 In USE SALT Complete parts. (a) through (e) after verifying that Ex = 16, 2y = 151, Ex = 78, y = 6,015, xy = 542, and r = -0.9340. (a) Draw a scatter diagram displaying the data. 6 SI 5 y (percentage) 3. 4 2 50 esc F1 2 F2 30 30 35 x (fouls) y (percentage) 2 6 5 1 40 45 30 35 40 45 x (fouls) APR 19 tv 50 80 F3 000 000 F4 F5 @ # 3 4 $ % 5 F6 & 7 ZOOM A G P W NEW 87 DI FB FB F10 00 9 0 B Profiles Tab Window Help X Math 1025 Wk 16: Prac HW CI x M Math 1025 Wk 15: Practice Qu x Cengage Learning webassign.net/web/Student/Assignment-Responses/last?dep=33455659#Q17 C Career School 50 45 y (percentage) 35 35 40 40 (b) Find x. X = 30 x (fouls) y (percentage) 501. 45 40 35 30 + x (fouls) 25 1 2 3 4 5 6 25 1 2 3 4 5 6 x (fouls) x (fouls) Find y (in %). % i Find the equation of the least-squares line = a + bx. (Round your numerical values to four decimal places.) = (c) Graph the least-squares line. Be sure to plot the point (x, y) as a point on the line. APR 1 19 tv 200M AG X P W NEW U Fri Apr 19 6: Relaunch to upda School sponses/last?dep=33455659#Q17 (c) Graph the least-squares line. Be sure to plot the point (x, y) as a point on the line. 50 45 y (percentage) 35 35 40 y (percentage) 30 y (percentage) 5 4 3 2 25 1 1 2 3 4 5 6 30 35 x (fouls) 6 5 3 2 1 A APR 19 1 tv y (percentage) 50+ 45 40 35 30 25 x (fouls) 40 45 zoom AG GO X W NEW U Rela 2 = 6 5 y (percentage) 3 4 2 X (100s) 50 45 30 y (percentage) 35 35 40 X (IOUIS) 1 25 30 35 40 45 1 2 3 4 5 6 x (fouls) x (fouls) (d) Find the value of the coefficient of determination 2. (Round your answer to four decimal places.) % What percentage of the variation in y can be explained by the corresponding variation in x and the least-squares line? (Round your answer to two decimal places.) What percentage is unexplained? (Round your answer to two decimal places.) % (e) If a team had x = 3 fouls over and above the opposing team, what does the least-squares equation forecast for y (in %)? (Round your answer to two decimal places.) % O APR 1 A 19