A Teacher Figures That Final Grades in the Chemistry Department $x ^ { 2 }$

Multiple Choice

A teacher figures that final grades in the chemistry department are distributed as: A, 25 % ; B, 25 % ; C, 40 % ;
D, 5 % ; F, 5 % . At the end of a randomly selected semester, the following number of grades were recorded.
Calculate the chi-square test statistic $x ^ { 2 }$ to determine if the grade distribution for the department is different than expected. Use $\alpha$

=0.01 .
$\begin{array} { l | l l l l l } \text { Grade } & \text { A } & \text { B } & \text { C } & \text { D } & \text { F } \\\hline \text { Number } & 42 & 36 & 60 & 14 & 8\end{array}$

A) 5.25
B) 6.87
C) 0.6375
D) 4.82