The following problem is reprinted from the November 1989 Actuarial Examination on Applied Statistical Methods. Source: Society of Actuaries.
You are given
$$\begin{array}{|c|cccc|}\hline {X} & {6.8} & {7.0} & {7.1} & {7.2} & {7.4} \\ \hline{Y} & {0.8} & {1.2} & {0.9} & {0.9} & {1.5}\\ \hline\end{array}$$
Determine $r^{2},$ the coefficient of determination for the regression of $Y$ on $X .$ Choose one of the following. (Note: The coefficient of determination is defined as the square of the correlation coefficient.)
a. $0.3 \qquad$ b. $0.4 \qquad$ c. $0.5 \qquad$ d. $0.6 \qquad$ e. $0.7$