eading proficiency: An educator wants to construct a 95 % confidence interval for the proportion of elementary school child Colorado who are proficient in reading. Part: 0 / 3 Part 1 of 3 (a) The results of a recent statewide test suggested that the proportion is 0.65. Using this estimate, what sample size is needed so that the confidence interval will have a margin of error of 0.06? A sample of elementary school children is needed to obtain a 95% confidence interval with a margin of error of 0.06. Save For Later Submit Assign