We ordered 3 pizzas. Each pizza has the same number of slices. If there were a total of 38 slices How many slices are there in each pizza?
There are 3 pizzas. 
Each pizza has the same number of slices. 
There are a total of 38 slices. 

We can set this up as an equation: 

3 pizzas * _____ slices/pizza = 38 slices

We can solve for the number of slices/pizza: 

3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices
3 pizzas * _____ slices/pizza = 38 slices