Nine Students Took the SAT Test $\text { Use } \alpha = 0.05 \text {. }$

Essay

Nine students took the SAT test. Later, they took a test preparation course and retook the SAT. Their original scores and new scores are shown below. Use the Wilcoxon signed rank test to test the claim that the test preparation had an effect on their scores. $\text { Use } \alpha = 0.05 \text {. }$ $$\begin{array} { l c c c c c c c c c } \hline \text { Student } & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 \\\hline \text { Before Score } 930 & 810 & 900 & 870 & 1120 & 910 & 940 & 980 & 1080 \\\text { After Score } & 950 & 810 & 890 & 910 & 1150 & 920 & 930 & 1020 & 1100 \\\hline\end{array}$$