On a final exam, a statistics instructor asked each her 62 students to estimate the number of texts he or she sent or received on an average day (x) and he correlated this with each student’s final grade in the course (y). The mean and standard deviation of x were mx = 82 and sx = 21, respectively. The estimated standard error of estimate was sest = 10. If the regression equation is 95 – 0.4(x), what is the 95% confidence interval for ŷ when x = 103?
[42.32, 57.41]
[22.98, 72.22]
[–12.31, 2.71]
[50.19, 57.41]
