There are 3 numbers. Add all of the weighted numbers together. To calculate the average of cells that meet one criteria use the AVERAGEIF function in Excel.
You should sum up all your values and divide by total number of those.
2 If calculating for a season divide by 7. For example we are given the total cost of preparation of three items. Distance x 2 x 1 2 y 2 y 1 2. The numbers of observations persons 3.