Confidence interval exercise
Given the following information
determine the 95% confidence interval for each mean:
N = 20, s2 = 9, M = 14.1
N = 30, s2 = 10, M = 98.9
N = 12, s2 = 6, M = 1.5
N = 25, s2 = 14, M = 16
Formula for 95% confidence interval:
M + 1.96 * (s/ √N)
observed mean plus and minus (1.96 times the (standard deviation divided by the square root of the sample size))