HSS.ID.A.4
Use the mean and standard deviation of a data set to fit it to a normal distribution and to estimate population percentages. Recognize that there are data sets for which such a procedure is not appropriate. Use calculators and/or spreadsheets to estimate areas under the normal curve.
Example Problems
What is the critical value for constructing a 90% confidence interval?
What is the critical value for constructing a 95% confidence interval?
What is the critical value for constructing a 94% confidence interval?
Khan Academy ResourcesBasic normal calculationsEmpirical ruleCalculating z-scoresNormal distribution: Area between two pointsNormal distribution: Area above or below a pointNormal calculations in reverseCalculate percentilesQualitative sense of normal distributionsNormal distribution problems: Empirical ruleCalculating percentileComparing with z-scoresFinding z-score for a percentileStandard normal table for proportion aboveStandard normal table for proportion between valuesStandard normal table for proportion belowZ-score introductionThreshold for low percentile

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