Question1. It is known that birth weights in the United States are normally distributed with a...

Question1. It is known that birth weights in the United States are normally

distributed with a mean of 3369 g and a standard deviation of 567 g. A premature or low-birth-

weight baby is often defined as a newborn baby whose birth weight is 2,500 g or less.

(i). What is the probability a baby will be born with low birth weight?

(ii). If a hospital typically has cribs for 100 newborn babies, what is the probability that average

birth weight of 100 newborns is greater than 3,500 g?

(iii). What is the 90% percentile of the average weights for 100 newborn babies?

(iv). If the shape of the distribution of birth weights is not normal (the mean and the standard

deviation remain the same), would the calculation in (ii) and (iii) still be valid? Why or why not?

Expert Solution

orchestra answered 2 years ago

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