Applicants for a Particular Job, Which Involves Extensive Travel in Spanish

Essay

Applicants for a particular job, which involves extensive travel in Spanish speaking countries, must take a proficiency test in Spanish. The sample data below were obtained in a study of the relationship between the numbers of years applicants have studied Spanish (x) and their score on the test (y).
$$\begin{array}{l}\begin{array} { l c c c c c c c c c c } \hline \mathrm { x } & 3 & 4 & 4 & 2 & 5 & 3 & 4 & 5 & 3 & 2 \\\hline \mathrm { y } & 57 & 78 & 72 & 58 & 89 & 63 & 73 & 84 & 75 & 48 \\\hline\end{array}\\\text { The regression equation } \hat { y } = 31.55 + 10.90 x \text { was obtained. Construct a residual plot for the }\end{array}$$