Answer:
675 will be stuffed crust.
Explanation:
The total number of pizzas sold initially is 1060 pizzas. Calculate the percentage of the stuffed crust pizzas within the 1060 pizzas.

Therefore the stuffed crust is 15% of the total sales.
To find how many pizzas she should expect to be stuffed crust pizzas in the next 4500, calculate 15% of 4500.

Therefore she should expect 675 pizzas of her next 4500 sales to be stuffed crust pizzas.