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Question: The number of chocolate chips in an


The number of chocolate chips in an 18-ounce bag of Chips Ahoy! chocolate chip cookies is approximately normally distributed, with a mean of 1262 chips and a standard deviation of 118 chips, according to a study by cadets of the U.S. Air Force Academy.
Source: Brad Warner and Jim Rutledge, Chance 12(1): 10–14, 1999.
(a) Determine the 30th percentile for the number of chocolate chips in an 18-ounce bag of Chips Ahoy! cookies.
(b) Determine the number of chocolate chips in a bag of Chips Ahoy! that make up the middle 99% of bags.
(c) What is the interquartile range of the number of chips in Chips Ahoy! cookies?


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