Linear regression Correlation coefficient

1-A sample of 12 houses that were sold last week in San Juan is selected.Can we conclude that, as the size of the house (reported in thousands of square feet in the
table below) increases, so does the sale price.
the following table in thousands of square feet), the selling price (reported in thousands of
dollars) also increases?
size of the house (thousandssales price (thousandssize
of of the house
of sq. ft.)
dollars)
(thousands of sq. ft.)
1.4
1.3
1.2
1.1
1.4
1.0
100
110
105
120
80
105
1.3
0.8
1.2
0.9
1.1
1.1
sales price (thousands of
dollars)
110
85
105
75
70
95
1. Calculate the correlation coefficient.
2. Calculate the coefficient of determination.
3. Determine the regression equation.
4. Is there a positive association between the size of the house and its selling price?
Use the 0.05 significance level.
Size of the house Sales price (thousands
(thousands of sq.
of dollars)
ft.)
1.40
100.00
1.30
110.00
1.20
105.00
1.10
120.00
1.40
80.00
1.00
105.00
1.30
110.00
0.80
85.00
1.20
105.00
0.90
75.00
1.10
70.00
1.10
95.00
Sales price (thou
130.00
120.00
110.00
100.00
90.00
80.00
70.00
60.00
0.60
0.70
Sales price (thousands of dollars)
y = 25.641x + 67.179
R² = 0.0944
0.80
0.90
1.00
1.10
1.20
1.30
1.40
1.50