The school band bought cheese and pepperoni pizzas in the ratio represented in the tape diagram for their end of year party. Based on the ratio how many pepperoni pizzas did they buy if they bought 12 cheese pizzas?

The cheese pizza is represented by 3 rectangles while the pepperoni pizza is represented by 1 rectangle.
Therefore, the ratio of cheese to pepperoni pizza is:
3 : 1
This means that if there are 3 cheese pizzas, then there will be 1 pepperoni pizza
Therefore, since they bought 12 cheese pizzas, it means that:
CCC + CCC + CCC + CCC = 12 cheese pizzas ( where C is cheese)
P + P + P + P = 4 pepperoni pizzas ( where P is pepperoni)
Thus, they bought 4 pepperoni pizzas