The number of chocolate chips in an? 18-ounce bag of chocolate chip cookies is approximately normally distributed with mean 1252 and standard deviation 129 chips.
?(a) What is the probability that a randomly selected bag contains between 1000 and 1500 chocolate? chips?
?(b) What is the probability that a randomly selected bag contains fewer than 1000 chocolate? chips?
?(c) What proportion of bags contains more than 1225 chocolate? chips?
?(d) What is the percentile rank of a bag that contains 1425 chocolate? chips?