I'm just starting Part 2 and haven't gotten to this section yet but if you are using Weighted average, to get answer D you will need to get the total sales for each product, sum them up and divide that total by the total # units. This will give you the weighted average CM. Then you divide the fixed cost by this weighted average contribution margin and that's how you get D
Total sales = CM * Number of Units sold
Product A = (10-4) * 15,000 = 90,000
Product B = (15-8) * 20,000 = 140,000
Product C = (18-9) * 5,000 = 45,000
Total sales = 90,000 + 140,000 + 45,000 = 275,000
Total units = 15,000 + 20,000 + 5,000 = 40,000
Weighted average Contribution Margin/unit = 275,000/40,000 = $6.875/unit
Break Even = FC/CM = 150,000/6.875 = 21,818 - answer D
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Laurence Heraux
Director/Manager
Chula Vista CA
United States
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