Computer store manager: Last year we made an average of 13 percent profit on the high-end computer models -- those priced over $1, 000 -- that we sold, while low-end models -- those priced below $1, 000 -- typically returned at least 25 percent profit  Since there is a limit to how many models we can display and sell, we should sell only low-end models
This would maximize our profits, since we would probably sell as many low-end models if that is all we sold as we would sell both kinds combined if we continued to sell both
The argument fails to consider the possibility that the money earned on each high-end computer is significantly higher than the money earned on each low-end computer.