In exercise 5, the following data on x = the number of defective parts found and y = the line speed (feet per minute) for a production process at Brawdy Plastics provided the estimated regression equation y = 27.5 – .3x.
Number of Defective
Line Speed Parts Found
20 ............. 23
20 ............. 21
30 ............. 19
30 ............. 16
40 ............. 15
40 ............. 17
50 ............. 14
50 ............. 11
For these data SSE = 16. Develop a 95% confidence interval for the mean number of defective parts for a line speed of 25 feet per minute.