A Biostatistician wants to conduct a survey among a population of teenage girls to estimate their...
A Biostatistician wants to conduct a survey among a population of teenage girls to estimate their
average protein intake (measured in grams). Assume that the population standard deviation
is 13.50 grams and he would like an interval to be 10 grams in width, then what is the sample
size necessary to ensure the confidence level to be 95%?
Homework Answers
From standard normal tables, we have here:
P(-1.96 < Z < 1.96) = 0.95
The margin of error is half the confidence interval width computed here as: 10/2 = 5
Therefore, we have here:
Therefore 29 is the minimum sample size required here.
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