Solution :
It is given that :
Vinnie owns a painting company having a fixed cost = $ 200
Quantity of houses painted per month Variable cost
1 $ 10
2 $ 20
3 $ 40
4 $ 80
5 $ 160
6 $ 320
7 $ 640
The efficient scale of the painting company = 4 house per month
as that minimizes the average total costs.
Total cost Average fixed cost
$ 200 -----
210 $ 200
220 100
240 66.67
280 50
360 40
520 33.33
840 28.57