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Giuseppi's pizza had orders for $931.00 of pizzas. the prices were $21 for a large pizza, 514 for a medium pizza, and $7 for a small pizza. the number of large pizzas was two less than four times the number of medium pizzas. thenumber of small pizzas was three more than three times the number of medium pizzas. how many of each size of pizza were ordered?

Find the solution of this system of equation -7x+y=-20 9x-3y=36

Your food costs are $5,500. your total food sales are $11,000. what percent of your food sales do the food costs represent?