1.

Given are five observations collected in a regression study on two variables.

x_i

2691320

y_i

91882521

(a)

Develop a scatter diagram for these data.

A scatter diagram has 5 points plotted on it. The horizontal axis ranges from 0 to 25 and is labeled:x. The vertical axis ranges from 0 to 30 and is labeled:y. The points are plotted from left to right in an upward, diagonal direction starting in the lower left corner of the diagram. The points are between 8 to 25 on the vertical axis and are fairly spread out.

A scatter diagram has 5 points plotted on it. The horizontal axis ranges from 0 to 25 and is labeled:x. The vertical axis ranges from 0 to 30 and is labeled:y. The points are plotted from left to right starting in the upper left corner of the diagram. Moving from left to right, the first 3 points appear to be plotted in an upward diagonal, direction while the next 2 points are much lower on the diagram.

A scatter diagram has 5 points plotted on it. The horizontal axis ranges from 0 to 25 and is labeled:x. The vertical axis ranges from 0 to 30 and is labeled:y. The points are plotted from left to right in a downward, diagonal direction starting in the upper left corner of the diagram. The points are between 8 to 25 on the vertical axis and are fairly spread out.

A scatter diagram has 5 points plotted on it. The horizontal axis ranges from 0 to 25 and is labeled:x. The vertical axis ranges from 0 to 30 and is labeled:y. The points are plotted from left to right in an upward, diagonal direction starting in the lower left corner of the diagram. The points are between 5 to 22 on the vertical axis and are fairly spread out.

(b)

Develop the estimated regression equation for these data.

?=

(c)

Use the estimated regression equation to predict the value ofywhenx=2.

2.

Brawdy Plastics, Inc., produces plastic seat belt retainers for General Motors at the Brawdy Plastics plant in Buffalo, New York. After final assembly and painting, the parts are placed on a conveyor belt that moves the parts past a final inspection station. How fast the parts move past the final inspection station depends upon the line speed of the conveyor belt (feet per minute). Although faster line speeds are desirable, management is concerned that increasing the line speed too much may not provide enough time for inspectors to identify which parts are actually defective. To test this theory, Brawdy Plastics conducted an experiment in which the same batch of parts, with a known number of defective parts, was inspected using a variety of line speeds. The following data were collected.

Line Number of Speed Defective Parts Found 20 23 20 21 30 20 30 15 40 15 40 17 50 13 50 12