The weight of a newborn baby is said to be normally distributed with a mean of 3.5kg and a standard deviation of 0.5kg. a. What weight marks the 80th percentile of newborn babies? (4 marks) b. What proportion of newborn babies weigh more than 3 standard deviations above the mean? (4 marks) c. Give the shape and parameters of the sampling distribution of the sample mean for a group of 10 newborn babies. Explain how you know the shape the distribution takes on. (4 marks) d. What is the probability that the average weight of a group of 10 new babies exceeds 3.7kg? (4 marks)
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The 80th percentile of a normal distribution is marked by a z-score of approximately 0.84. Show more…
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