A2.25.b
Estimate areas under a normal curve to solve problems in context, using calculators, spreadsheets, and tables as appropriate.
Example Problems
The grades on a biology midterm at Northgate are roughly symmetric with and . Lucas scored 65 on the exam.
Find the z-score for Lucas's exam grade.
Round to two decimal places.
Find the z-score for Lucas's exam grade.
Round to two decimal places.
The grades on a music theory midterm at Kingsley are roughly symmetric with and . Ava scored 60 on the exam.
Find the z-score for Ava's exam grade.
Round to two decimal places.
Find the z-score for Ava's exam grade.
Round to two decimal places.
The grades on a literature midterm at Pinecrest are roughly symmetric with and . Liam scored 86 on the exam.
Find the z-score for Liam's exam grade.
Round to two decimal places.
Find the z-score for Liam's exam grade.
Round to two decimal places.
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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