Confidence intervals for population means

E zyBooks E ? Suppose the mean height in inches of all 9th grade students at one high school is 2 estimated. The population standard deviation is 5 inches. The heights of 8 randomly selected students are 67, 71, 75, 61, 66, 61, 70 and 61. D = EX: 12.34 Margin of error at 90% confidence level = Ex: 1.23 90% confidence interval = [ Ex: 12.34 Ex: 12.34 [smaller value, larger value]