Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The city of Oakdale wishes to see if there is a linear relationship between the

ID: 3238512 • Letter: T

Question

The city of Oakdale wishes to see if there is a linear relationship between the temperature and the amount of electricity used (in kilowatts).   Based on the data in the table below, is there a significant linear relationship between temperature and the amount of electricity used? These data are also available in the worksheet temperature in the Excel workbook Temperature.xlsx.

Temperature.xlsx

Temperature (x)

73

78

85

98

93

81

76

105

Kilowatts (y)

680

760

910

1510

1170

837

600

1800

Temperature (x)

73

78

85

98

93

81

76

105

Kilowatts (y)

680

760

910

1510

1170

837

600

1800

Explanation / Answer

ANS= c

X Values
= 689
Mean = 86.125
(X - Mx)2 = SSx = 912.875

Y Values
= 8267
Mean = 1033.375
(Y - My)2 = SSy = 1274757.875

X and Y Combined
N = 8
(X - Mx)(Y - My) = 33461.625

R Calculation
r = ((X - My)(Y - Mx)) / ((SSx)(SSy))

r = 33461.625 / ((912.875)(1274757.875)) = 0.9809

Meta Numerics (cross-check)
r = 0.9809

r=0.981

Yes, the sample correlation coefficient is equal to 0.981, which provides evidence of a significant linear relationship.

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote