Goodness-of-Fit Test · Exercise 8

A teacher predicts the distribution of grades on the final exam. The predictions are shown in.
$$\begin{array}{cc}\text{Grade}& \text{Proportion}\\ \text{A}& \text{0.25}\\ \text{B}& \text{0.30}\\ \text{C}& \text{0.35}\\ \text{D}& \text{0.10}\end{array}$$

The actual distribution for a class of 20 is in.
$$\begin{array}{cc}\text{Grade}& \text{Frequency}\\ \text{A}& \text{7}\\ \text{B}& \text{7}\\ \text{C}& \text{5}\\ \text{D}& \text{1}\end{array}$$

At the 5 percent significance level, what can you conclude?

OpenStax, Statistics · §11.2 Goodness-of-Fit Test · Exercise 8