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Below are four bivariate data sets and their scatter plots. (Note that all of the scatter plots are displayed with the same scale. ) Each data set is made up of sample values drawn from a population. x y 11 - u V 11 - 1.0 4.1 10 - 1.0 8.1 10 - X X 2.0 5.7 9 X 2.0 5.0 9-- X 8 - X 8- X 3.0 6.5 X 7- X 3.0 9.6 7-+ X X 4.0 4.7 X 6 - 6- X X 4.0 6.3 5 - 5.0 4.5 X X 5.0 2.4 5- X X 4_ X 6.0 8.2 3 - 6.0 5.2 3-+ X X 7.0 15.8 2 - 8.5 2 - 8.0 6.9 8.0 3.3 9.0 8.8 9.0 9.9 3 9 10 11 10.0 7.4 Figure 1 10.0 6.6 Figure 2 W t m n 1.0 3.2 10 - 1.0 8.0 10- 2.0 4.1 9 - 2.0 7.0 9 - 8 - X X 8- X 3.0 3.8 Y 3.0 7.6 X 7- X 7- X X 4.0 4.9 6- 4.0 6.1 6- Y X 5.0 4.7 5 - X X 5.0 6.6 X X 4 - X X X 6.0 17.1 3 - X 6.0 4.5 X X 5.6 2 - 7.0 5.1 8.0 8.1 8.0 3.1 9.0 7.4 $ 8 + 8 , 10 11 9.0 4.0 0 10 11 10.0 8.2 Figure 3 10.0 2.9 Figure 4Below are four bivariate data sets and their scatter plots. (Note that all of the scatter plots are displayed with the same scale. ) Each data set is made up of sample values drawn from a population. X y u V 1.0 10 - 1.0 10.0 10 - X 2.0 6.8 9- 2.0 9.0 9 - X 8 - X 8 - X X 3.0 7.8 7- 3.0 8.0 Y X 4.0 6.0 X 4.0 7.0 X 5.0 7.2 5.0 6.0 X X X X X 6.0 4.3 X 6.0 5.0 3- X 7.0 5.3 2- 7.0 4.0 X 8.0 4.0 8.0 3.0 X 9.0 4.6 0 89 9.0 2.0 8 11 10.0 3.4 Figure 1 10.0 1.0 Figure 2 W 11 - m n 1.0 8.0 10 - X 1.0 4.1 10- 9_ X 2.0 5.1 X 2.0 6.1 9_ X 8 - X 8 - X 3.0 10.0 3.0 7.4 X X X 7- X 4.0 6.0 X 4.0 4.7 X X X X X 5 - 5.0 1.9 5.0 5.4 X 4_ X 6.0 5.5 3 - X 6.0 8.1 3- 7.0 9.0 X 7.0 5.4 8.0 3.4 8.0 7.3 9.0 9.4 5 6 7 8 8 10 1 1 7 9.0 8.7 10.0 6.6 Figure 3 10.0 7.7 Figure 4Mileage, x Used selling price, y (in thousands) (in thousands of dollars) 4o - 35 - 30 _- X 25 __ Used selling price (in thousands of dollars) xx 20 __ / X //llllll> 15 20 25 30 35 40 Mileagex (in thousands) Send data to calculator v Sleep time, y GAS score, x _ xy (In hours) 3.7 7.9 29.23 2.9 7.1 20.59 y 6.6 5.8 38.28 10\" 8.9 6.0 53.4 9-. 3.9 6.6 25.74 X X X a) A x 5.0 6.3 31.5 E e 8- x a: 5 1.5 8.4 12.6 32 7_ x x x 2 .E x x 1.1 7.2 7.92 U) v x 6_ x 3.9 8.3 32.37 x x 8.2 5.5 45.1 5-- 8.0 7.1 56.8 . . . . . " u 2' 4' 6' 8' 16 2.0 8.1 16.2 GAS score 9.0 5.5 49.5 Figure 1 6.9 6.6 45.54 6.1 8.4 51.24 Send data to calculator v ) What is the slope of the least-squares regression line for these data? Carry your intermediate computations to at least four decimal places and round your answer to at least two decimal places. (If necessary, consult a list of formulas.) Standardized Grade point test score, x average, y xy 1190 2.95 3510.5 850 2.28 1938 1390 3.03 3.8- 4211.7 X 3.6- 900 2.71 2439 3.4- X 1280 2.97 3801.6 3.2- X X 1260 3.11 3918.6 3 - X X X X 2.8- 800 2.32 1856 Grade point average X 2.6- 1010 2.45 2474.5 X 2.4- X X X 1510 3.10 4681 2.2- X 2-+ 1060 2.96 3137.6 1.8- 950 2.28 2166 800 900 1000 1100 1200 1300 1400 1500 1000 3.00 3000 Standardized test score 1110 2.11 2342.1 Figure 1 1350 3.75 5062.5 1510 3.30 4983 Send data to calculator V What is the sample correlation coefficient for these data? Carry your intermediate computations to at least four decimal places and round your answer to at least three decimal places. (If necessary, consult a list of formulas.)Consider the following random sample of diameter measurements (in inches) of 9 softballs. 4.86, 4.89, 4.72, 4.68, 4.73, 4.72, 4.85, 4.85, 4.77 Send data to calculator If we assume that the diameter measurements are normally distributed, find a 99% confidence interval for the mean diameter of a softball. Then find the lower limit and upper limit of the 99% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to two decimal places. (If necessary, consult a list of formulas.) Lower limit: _ X 5 ? Upper limit:We want to conduct a hypothesis test of the claim that the population mean reading speed of second graders is different from 29.7 words per minute. So, we choose a random sample of students' reading speeds. The sample has a mean of 29.5 words per minute and a standard deviation of 3.2 words per minute. For each of the following sampling scenarios, choose an appropriate test statistic for our hypothesis test on the population mean. Then calculate that statistic. Round your answers to two decimal places. (a) The sample has size 105, and it is from a non-normally distributed population with a known standard deviation of 2.7. 02=D xt=D It is unclear which test statistic to use. (b) The sample has size 13, and it is from a normally distributed population with an unknown standard deviation. _z=|:| xt=D It is unclear which test statistic to use. We want to conduct a hypothesis test of the claim that the population mean score on a nationwide examination in biology is different from 515. So, we choose a random sample of exam scores. The sample has a mean of 514 and a standard deviation of 80. For each of the following sampling scenarios, choose an appropriate test statistic for our hypothesis test on the population mean. Then calculate that statistic. Round your answers to two decimal places. (a) The sample has size 10, and it is from a normally distributed population with an unknown standard deviation. \\ZZD "=D " It is unclear which test statistic to use. (b) The sample has size 11, and it is from a normally distributed population with a known standard deviation of 77. _Z=|:| \"FD ' ' It is unclear which test statistic to use
