Using a Three-Month Moving Average, the Forecast Value for October

Multiple Choice

Using a three-month moving average, the forecast value for October made at the end of September in the following time series would be ____________. $$\begin{array} { | r | r | } \hline \text { July } & 5 \\\hline \text { Amg } & 11 \\\hline \text { Sent } & 13 \\\hline \text { Oct } & 6 \\\hline\end{array}$$

A) 11.60
B) 10.00
C) 9.07
D) 8.06
E) 9.67