When the price of pizza was $10.00 for a medium pizza, students at a college consumed 400 pizzas per week. When the price of pizza increased to $30.00 for a medium pizza, students at a college consumed 100 pizzas per week. Calculate the price elasticity of demand for medium pizzas for the students. You must show your work to receive credit for your calculation. If the price of pizza increases by 1%, by what will the percentage change in quantity demanded of pizzas for the students?