Problem $3-4($Algo$)$

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

$\backslash$table$[[,$LAST YEAR,THIS YEAR$],[$January$,320,295],[$February$,380,370],[$March$,420,362],[$April$,425,465],[$May$,440,430],[$June$,475,375],[$July$,440,375],[$August$,310,315],[$September$,375,385],[$October$,540,],[$November$,575,],[$December$,555,]]$

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 $0\mathrm{.}25.$ Solve the problem using quarters, as opposed to forecasting separate months.

Note: Round your answer to $2$ decimal places.

Forecast for the fourth quarter