Total number of model cars Cameron has = 12
According to the above statement, each of the 8 shelves display 1 car. This means the 8 shelves display 8 cars in total. Cameron has total 12 cars. 8 out of these 12 cars are already being displayed, so he is left with 4 cars.
The remaining cars are to be displayed with 2 cars on a shelf. Since there are 4 cars remaining, Cameron needs to more shelves to display these 4 cars.
Therefore, the answer to this question is:
2 shelves will display 2 cars each.
