Here is the data for the last $21$ months of actual sales for a particular product:

Month Last Year This Year Month Last Year This Year

January $300275$ July $400350$

February $400375$ August $300275$

March $425350$ September $375350$

April $450425$ October $500$

May $400400$ November $550$

June $460350$ December $500$

Develop a forecast for the fourth quarter using a currency$-$weighted moving

average third trimester. Weight most recent quarter as $0\mathrm{.}5,$ second most

recent as $0\mathrm{.}25$ and the third as $0\mathrm{.}25.$ Solve the problem using quarters, as

opposed to forecasting each month. $(15$ po