Q:

Many high school students take either the SAT or the ACT. However, some students take both. Data were collected from 60 students who took both college entrance exams. The average SAT score was 912 with a standard deviation of 180. The average ACT score was 21 with a standard deviation of 5. The correlation between the two variables equals 0.817. To predict the SAT score from a student's ACT score, what is the equation of the least-squares regression line?'

Accepted Solution

A:
Answer:0.6675Step-by-step explanation:Given that many high school students take either the SAT or the ACT.However, some students take both. Data were collected from 60 students who took both college entrance exams.                            SAT score            ACT score with a  of 180.Average                    912                      21 standard deviation   180                        5Correlation between the two variables r = 0.817WE have for two variables if we have correlation coefficient then the square of correlation coefficient gives the fraction of variation in the values of the SAT scores is accounted for by the linear relationship between the SAT and ACT scoresSo we find square of r[tex]r^2 =0.817^2\\=0.6675[/tex]i.e. 0.6675 or 66.75% of the variation in the values of the SAT scores is accounted for by the linear relationship between the SAT and ACT scores