Malnutrition and Poverty. R. Reifen et al. studied various nutritional measures of Ethiopian school children and published their findings in the paper “Ethiopian-Born and Native Israeli School Children Have Different Growth Patterns” (Nutrition, Vol. 19, pp. 427– 431). The study, conducted in Azezo, North West Ethiopia, found that malnutrition is prevalent in primary and secondary school children because of economic poverty. The weights, in kilograms (kg), of 60 randomly selected male Ethiopian-born school children aged 12– 15 years old are presented in increasing order in the following table.
The sample
- a. Is it reasonable to apply the
empirical rule to estimate the percentages of observations that lie within one, two, and three standard deviations to either side of the mean? - b. Use the empirical rule to estimate the percentages of observations that lie within one, two, and three standard deviations to either side of the mean.
- c. Use the data to obtain the exact percentages of observations that lie within one, two, and three standard deviations to either side of the mean.
- d. Compare your answers in parts (b) and (c).
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