



 
Hi Andrew, The subject line of your email suggested that you were expecting to use the Normal Distribution to solve this problem. I don't think you should try to use the Normal Distribution. I expect you are to take the statement "Looking over your past 12,421 pizza deliveries you find out 97% of the pizzas were delivered in 30 minutes or less." to mean that the probability that a pizza is delivered on time is 0.97. I think you are also expected to assume that the pizza deliveries are independent so that the probability of delivering a pizza on time is 0.97 regardless of what has happened on the previous deliveries. This allows you to use the multiplication rule. Can you complete the problem now? Write back if you need further assistance,  


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