Please help me with these statistics questions for my homework.... I'm so confused and don't understand :(
1)
Bivariate data for the quantitative variables x and y are given in the table below. These data are plotted in the scatter plot shown next to the table. In the scatter plot, sketch an approximation of the least-squares regression line for the data. X y 9.1 2.8 11- 3.0 9.8 1.4 10.7 10- 7.8 3.7 9 X 4.6 7.9 5 ? 5.7 4.5 9.8 2.3 7- 7.4 4.4 6- 8.4 3.1 3.2 7.9 4.0 7.2 6.7 5.5 3-+ 5.7 7.1 2.4 8.9 2- 2.1 10.1 1 - 7.1 3.9 10.2 1.7 2 3 6 8 9 10 11 5.1 6.3A popular, nationwide standardized test taken by high-school juniors and seniors may or may not measure academic potential, but we can nonetheless examine the relationship between scores on this test and performance in college. We have chosen a random sample of fifteen students just finishing their first year of college, and for each student we've recorded her score on this standardized test (from 400 to 1600) and her grade point average (from 0 to 4) for her first year in college. The data are shown below, with x denoting the score on the standardized test and y denoting the first-year college grade point average. A scatter plot of the data is shown in Figure 1. Also given is the product of the standardized test score and the grade point average for each of the fifteen students. (These products, written in the column labelled "xy", may aid in calculations.) Standardized Grade point test score, X xy average, y 1490 3.11 4633.9 1190 2.62 3117.8 980 2.36 2312.8 1060 2.79 2957.4 34- 1290 3.01 3882.9 32- 1100 2.18 2398 23- 780 2.29 1786.2 Grade point average 2.6- 1490 3.54 5274.6 24+ 1010 3.08 3110.8 22- 2- 1400 3.18 4452 13+ 860 2.12 1823.2 + 800 900 1000 1100 1200 1300 1400 1500 1240 3.15 3906 Standardized test score 910 2.61 2375.1 Figure 1 940 2.19 2058.6 1360 3.73 5072.8 Send data to calculator Send data to Excel 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 four decimal places. (If necessary, consult a list of formulas.)Bivariate data for the quantitative variables x and y are given in the table below. These data are plotted in the scatter plot shown next to the table. In the scatter plot, sketch an approximation of the leastsquares regression line for the data. x l' 3.4 9.9 13 2.3 6.4 2.3 9.4 9.? 1.6 2.3 5.3 4.4 9.1 3.6 2.9 3.3 5.7 5.3 4.4 3.3 5\" x X 1.7 1.4 4 xx x 6.6 6.4 9.9 10.3 15 6.9 2-- x 2.3 1.9 l__ x 3.2 3.9 1 I I I I I I I I I I I 3'9 4'6 ] 2 3 4 S 5 TI' 8 9 ii] [1 6.9 2.? 4* The scatter plot shows the time spent texting, x, and the time spent exercising, y, by each of 23 students last week. (a) Write an approximate equation of the line of best t for the data. It doesn't have to be the exact line of best t. (b) Using your equation from part (a), predict the time spent exercising for a student who spends 6 hours texting. Note that you can use the graphing tools to help you approximate the line. 'I'Ime spent exercising (in hours) Tlme spent texting (in hours) 29%: XS)? (a) Write an approximate equation of the line of best t. y: (b) Using your equation from part (a), predict the time spent exercising for a student who spends 6 hours texting. hours
