The number of pizzas is in a proportional relationship to the weight of the shredded cheese toppings. When​ shredded, a​ 50-lb block of cheese is enough to make 150 large pizzas. Find the constant of proportionality. Use pencil and paper. Explain how you can use a constant of proportionality to find how much cheese is on one slice of pizza if there are 8 slices per pizza.