An oven can cook 3 thin crust pizzas in an hour or 1 deep dish pizza in a hour. If you have one oven, how much time do you need to make 12 thin crust pizzas and 4 deep dish pizzas?
It would take you 4 hours to make 12 thin crust pizzas and 4 hours to make 4 deep dish pizzas. all in total your time would be 8 hours 12/3=4 4/1=4 4+4=8