# Modeling data distributions

## Percentiles

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Calculating percentileAnalyzing a cumulative relative frequency graphCumulative relative frequency graph problem
Practice
Calculating percentilesGet 3 of 4 questions to level up!

## Z-scores

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Normal distribution problem: z-scores (from ck12.org)Comparing with z-scoresZ-scores review
Practice
Calculating z-scoresGet 3 of 4 questions to level up!

## Effects of linear transformations

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How parameters change as data is shifted and scaledTransforming data problem
Practice
Transforming dataGet 3 of 4 questions to level up!

## Density curves

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Density CurvesMedian, mean and skew from density curvesDensity curve worked exampleWorked example finding area under density curves
Practice
Properties of density curvesGet 3 of 4 questions to level up!
Area under density curvesGet 3 of 4 questions to level up!

## Normal distributions and the empirical rule

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Qualitative sense of normal distributions (from ck12.org)Normal distribution problems: Empirical rule (from ck12.org)Standard normal distribution and the empirical rule (from ck12.org)More empirical rule and z-score practice (from ck12.org)Normal distributions review
Practice
Empirical ruleGet 3 of 4 questions to level up!

## Normal distribution calculations

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Standard normal table for proportion belowStandard normal table for proportion aboveStandard normal table for proportion between valuesFinding z-score for a percentileThreshold for low percentileBasic normal calculations
Practice
Normal distribution: Area above or below a pointGet 3 of 4 questions to level up!
Normal distribution: Area between two pointsGet 3 of 4 questions to level up!
Normal calculations in reverseGet 3 of 4 questions to level up!

## More on normal distributions

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Deep definition of the normal distributionNormal distribution excel exercise