The Table Below Shows the Demand for Fidgets (They're Like

Essay

The table below shows the demand for Fidgets (they're like Widgets, only they're more active) over an eight-month period. Calculate a four-period moving average forecast for September. Also evaluate the quality of the four-period moving average forecasting model by calculating the root-mean-square error for the data set. Note: Round all intermediate calculations to two decimal places.
$$\begin{array} { c c } \text { Month } & \text { Demand } \\\text { Jan } & 10 \\\text { Feb } & 11 \\\text { Mar } & 5 \\\text { Apr } & 8 \\\text { May } & 6 \\\text { Jun } & 11 \\\text { Jul } & 5 \\\text { Aug } & 11\end{array}$$