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The ages of a group of 140 randomly selected adult females have a standard deviation of 17.2 years. Assume that the ages of female statistics students have less variation than ages of females in the generalpopulation, so let =17.2 years for the sample size calculation. How many female statistics student ages must be obtained in order to estimate the mean age of all female statisticsstudents? Assume that we want 98% confidence that the sample mean is withinone-half year of the population mean. Does it seem reasonable to assume that the ages of female statistics students have less variation than ages of females in the generalpopulation?

The required sample size is

(Round up to the nearest whole number asneeded.)