The data below are the final exam scores of 10 randomly selected statistics students and the number of hours they studied for the exam. Calculate the correlation coefficient r. $$\begin{array} { l | c | c | c | c | c | c | c | c | c | c | }
\text { Hours, } \mathrm { x } & 2 & 4 & 1 & 7 & 1 & 3 & 3 & 4 & 5 & 2 \
\hline \text { Scores, } y & 68 & 83 & 63 & 91 & 69 & 81 & 88 & 93 & 93 & 74
\end{array}$$
A)0.847
B)0.991
C)0.761
D)0.654

Question

The data below are the final exam scores of 10 randomly selected statistics students and the number of hours they studied for the exam. Calculate the correlation coefficient r. $$\begin{array} { l | c | c | c | c | c | c | c | c | c | c | } 
\text { Hours, } \mathrm { x } & 2 & 4 & 1 & 7 & 1 & 3 & 3 & 4 & 5 & 2 \
\hline \text { Scores, } y & 68 & 83 & 63 & 91 & 69 & 81 & 88 & 93 & 93 & 74
\end{array}$$
A)0.847
B)0.991
C)0.761
D)0.654

Quizplus · Accepted Answer

The correlation coefficient $r$ measures the strength and direction of a linear relationship between two variables. It's calculated using a specific formula that considers the means and standard deviations of both variables, as well as their covariance. Given the data provided, calculating $r$ manually or using statistical software should yield a result close to 0.847, indicating a strong positive correlation between hours studied and exam scores.

The Data Below Are the Final Exam Scores of 10