CHALLENGE ACTIVITY 5.7.1: Confidence intervals for population means. 353727 1043571p Gam/7 Jump to level 1 1 Suppose the mean height in inches of all 9th grade students at one high school is estimated. The population standard deviation is 2 inches. The heights of 9 randomly selected students are 73, 75, 65, 70, 62, 70, 72, 60 and 72. T = Ex: 12.349 Margin of error at 90% confidence level = Ex: 1.23 90% confidence interval = [ Ex: 12.34 Ex: 12.34 [smaller value, larger value] 1 Check Next Feedback