A Teacher Finds That Final Grades in the Statistics Department $25 \% ; \mathrm { C } , 40 \%$

question 37

Essay

A teacher finds that final grades in the statistics department are distributed as: A, 25\%; B, $25 \% ; \mathrm { C } , 40 \%$ ; D, 5\%; F, 5\%. At the end of a randomly selected semester, the following grades were recorded. Determine if the grade distribution for the department is different than expected. Use $\alpha = 0.01$ .
$\begin{array}{l|lllll}\text { Grade } & \text { A } & \text { B } & \text { C } & \text { D } & \text { F } \\\hline \text { Number } & 36 & 42 & 60 & 8 & 14\end{array}$

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Definitions:

Supply Curve

A graph displaying the relationship between the price of a good or service and the quantity of that good or service that a supplier is willing and able to provide, holding all else equal.

Diminishing Marginal Product

A principle stating that as more of a variable input is added to a fixed input, the additional output produced from each additional unit of the variable input eventually decreases.

Marginal Costs

The supplementary cost arising from the manufacture of an extra unit of a good or service.

Variable Inputs

Inputs that can be adjusted in the short term to alter the level of output in the production process.