Problem $18-4($Algo$)$

Here are the data for the past $21$ months for actual sales of a particular product:

Develop a forecast for the fourth quarter using a three$-$quarter, weighted moving average. Weight the most recent quarter $0\mathrm{.}50,$ the

second most recent $0\mathrm{.}25,$ and the third $0\mathrm{.}25.$ Do the problem using quarters, as opposed to forecasting separate months. $($Round your

answer to $2$ decimal places.$)$

Forecast for the fourth quarter