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Subjects / LC Mathematics / Statistics and Probability

The normal distribution, empirical rule and z-scores

Use the empirical rule and, at Higher Level, z-scores and tables to find probabilities for normal data.

In review 5th Year6th Year HigherOrdinary
Helps to know first: Measures of centre and spread
15practice questions

Multiple choice: 2 · Select all that apply: 1 · Numeric answer: 11 · Written answer (self/teacher assessed): 1

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Numeric answerPaper 2 – Statistics and Probability
A variable is normally distributed with mean 46 and standard deviation 17. Find the z-score of the value 54.5.
μ−2σμ−σμμ+σμ+2σ
Whole numbers, decimals (2.5) or fractions (3/4).
Hint 1

z = (x − μ)/σ.

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