SC 65 c140 dsce90 y0 Round to thene deciesal places as neede

SC 65 c140 (d)sce90 y-0- Round to thene deciesal places as needed Constract a scater plot of the dats and daw the oegression e Plot shoe size on the herizestal w Oa Choose the conrect graph belew Or and bright on the vetical On a) Predict the valse of y for -6.3.Choose the eeerect anaer below OA 636 OB 662 OC 685 b) Predict the valur of y for -7.0 Choose the correct wwwe be

Solution

Step 1: Find XY and X² as it was done in the table below.

X

Y

XY

XX

6

65

390

36

10

68

680

100

11

79

869

121

11.5

71

816.5

132.25

12.5

74

925

156.25

13.5

72

972

182.25

Step 2: Find the sum of every column:

X=64.5 , Y=429 , XY=4652.5 , X²=727.75

Step 3: Use the following equations to find a and b:

a=[(YX²XXY)/(nX²(X)²)]=429727.7564.54652.56727.7564.5258.756

b=[(nXYXY)/(nX²(X)²)]=64652.564.54296727.75(64.5)21.185

Step 4: Substitute a and b in regression equation formula

y = a + bx

                    y   = 58.756 + 1.185x

(a) For x = 6.5 , y = 66.4585

(b) For x = 7.0 , y = 67.051

(c) For x =14.0 , y = 75.346

(d) For x = 9.0 , y = 69.421

The graph is given by (b)

X	Y	XY	XX
6	65	390	36
10	68	680	100
11	79	869	121
11.5	71	816.5	132.25
12.5	74	925	156.25
13.5	72	972	182.25