As with many other construction materials, the price of gravel (per ton) depends on the quantity of material ordered. The following table presents the unit cost (dollars/ton) for gravel for various order sizes (in tons).
$\begin{array} { c c }
\hline \text { Tons of Gravel } & \text { Unit Cost (dollars/ton) } \
\hline 10 & 30.44 \
47 & 18.99 \
60 & 17.31 \
61 & 16.85 \
22 & 22.80 \
60 & 17.71 \
58 & 18.12 \
39 & 19.59 \
74 & 17.35 \
59 & 18.00 \
\hline
\end{array}$
Compute the coefficient of determination.
A)0.8270
B)-0.9094
C)-0.0906
D)0.1730

Question

As with many other construction materials, the price of gravel (per ton) depends on the quantity of material ordered. The following table presents the unit cost (dollars/ton) for gravel for various order sizes (in tons).
 $\begin{array} { c c } 
\hline \text { Tons of Gravel } & \text { Unit Cost (dollars/ton) } \
\hline 10 & 30.44 \
47 & 18.99 \
60 & 17.31 \
61 & 16.85 \
22 & 22.80 \
60 & 17.71 \
58 & 18.12 \
39 & 19.59 \
74 & 17.35 \
59 & 18.00 \
\hline
\end{array}$
Compute the coefficient of determination.
A)0.8270
B)-0.9094
C)-0.0906
D)0.1730

Quizplus · Accepted Answer

The coefficient of determination, often denoted as $R^2$, measures the proportion of the variance in the dependent variable that is predictable from the independent variable. In this context, it would reflect how well the quantity of gravel ordered can predict the unit cost. Given the nature of the question, without the actual calculations shown (which would involve calculating the correlation coefficient $r$ and then squaring it to get $R^2$), the correct answer is chosen based on the understanding that $R^2$ values range from 0 to 1, where 1 indicates a perfect fit. Negative values are not possible for $R^2$, making A the correct choice.

As with Many Other Construction Materials, the Price of Gravel