Posted by natasha on .
A studyis run to estimate the mean total cholesterol level in children 2 to 6 years of age. A sample of 9 participants is selected and their total cholesterol levels are measured as follows:
185 225 240 196 175 180 194 147 223
Generate a 95% confidence interval for the true mean total cholesterol leels in children.

biostatistics 
PsyDAG,
95% confidence interval = mean ± 1.96 SEm
SEm = SD/√n
Find the mean first = sum of scores/number of scores
Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.
Standard deviation = square root of variance
I'll let you do the calculations.