A Biology Professor Claims That, on the Average, 15% of Her

Multiple Choice

A biology professor claims that, on the average, 15% of her students get a grade of A, 20% get a B, 40% get a C, 15% get a D, and 10% get an F. The grades of a random sample of 135 students were Recorded. The following table presents the results.

$\begin{array} { c | l l l l l } \text { Grade } & 1 & 2 & 3 & 4 & 5 \\\hline \text { Observed } & 14 & 13 & 48 & 43 & 17\end{array}$

What is the value of $\chi ^ { 2 }$ ?

A) 9.488
B) 37.333
C) 11.143
D) 36.321