In a manufacturing process the assembly line speed (feet per Minute) was thought to affect the number of defective parts found during the inspection process. To test this theory, management devised a situation where the same batch of parts was inspected visually at a variety of line speeds. The following data were collected

Line Speed Number of Defective

Parts Found

20 21
20 19
40 15
30 16
60 14
40 17

a. Develop a scatter diagram.

b. Show correlation at the 0.05 significance level.

c. Develop the regression line for the data.

d. Add the regression line to your scatter diagram.

e. What number of defectives would you expect to be found at a line speed of 50?