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Attempt 5 Birthweight is studied because low birthweight is an indicator of infant mortality. A study of babies in Norway published in the International Journal of Epidemiology shows that birthweight of full-term babies (37 weeks or more of gestation) are very close to normally distributed with a mean of 3600 g and a standard deviation of 600 g. Suppose that Melanie is a researcher who wishes to estimate the mean birthweight of full-term babies in her hospital. What is the minimum number of babies should she sample if she wishes to be at least 95% confident that the mean birthweight of the sample is within 180 g of the the mean birthweight of all babies? Assume that the distribution of birthweights at her hospital is normal with a standard deviation of 600 g. n = 25.0 Incorrect Source: International Journal of Epidemiology, July 30, 2001. On the importance - and the unimportance - of birthweight. http://ije.oxfordjournals.org/content/30/6/1233.full (accessed April 18, 2016)