posted by Anonymous .
The heights (in feet) of a sample of five randomly chosen students from School x are 6.3, 6.1, 5.7, 5.8, and 6.2. Determine a 90% confidence interval for the mean height of all students at School x
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
90% = mean ± 1.645 SEm
SEm = SD/√n
I'll let you do the calculations.