NW 39. Chips Ahoy! Cookies 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 standard deviation...

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Extracted text: NW 39. Chips Ahoy! Cookies 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 standard deviation 118 chips according to a study by cadets of the US Air Force Academy Source: Brad Warner and Jim Rutledge, Chance 12(1): 10-14, 1999 (a) What is the probability that a randomly selected 18-ounce bag of Chips Ahoy! contains between 1000 and 1400 chocolate chips, inclusive? (b) What is the probability that a randomly selected 18-ounce bag of Chips Ahoy! contains fewer than 1000 chocolate chips? (c) What proportion of 18-ounce bags of Chips Ahoy! contains more than 1200 chocolate chips? (d) What proportion of 18-ounce bags of Chips Ahoy! contains fewer than 1125 chocolate chips? (e) What is the percentile rank of an 18-ounce bag of Chips Ahoy! that contains 1475 chocolate chips? What is the percentile rank of an 18-ounce bag of Chips Ahoy! that contains 1050 chocolate chips?