Question

In a previous study, 180 randomly selected adult males had their weights taken that resulted in a standard deviation of 18.05 kg. Current researchers plan to study the weights of male medical students. How many male medical students must be weighed to estimate the mean weight of all male medical students? They have assumed that weights of male medical students have less variation than weights of the population of adult males and plan to let σ = 18.05 kg. Additionally, the want to be 92% confident that the sample mean is within 1.8 kg of the population mean. 

A. Minimum sample size needed: _______ 

B. Does it seem reasonable to assume that weights of male medical students have less variation than weights of the population of adult males?

 i. Yes, as male medical students tend to weigh less than adult males in general.

 ii. Yes, as the dispersion in weights in a defined sub-group should be smaller than in the general population.

 iii. No, since nothing is known about the difference in weights of the students and population.

 iv. No, as that assumption is not conservative enough for this study.

 v. None of the above.

Answer 1

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