Here are the data for the past 21 months for actual sales of a particular prod

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

Last Year

This Year

January

300

275

February

400

375

March

425

350

April

450

425

May

400

400

June

460

350

July

400

350

August

300

275

September

375

350

October

500

November

550

December

500

Develop a forecast for the fourth quarter using a three-quarter weighted moving average. Weight the most recent quarter .5 the second most recent .25
and the third .25. Do the problem using quarters as opposed to forecasting separate months.