AP Statistics
AP Statistics 2012 Actual Test and Answer Key (Multiple Choice and FRQs)
AP Statistics Formula Sheet (2019)
Confidence Interval Formulas:
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Using Standard Deviation of a Sample
Conf Interval-Low Boundary = Mean - (z-value)(Standard Deviation) / (square root of sample size)
Conf Interval-High Boundary = Mean + (z-value)(Standard Deviation) / (square root of sample size)
Using Standard Deviation of the Underlying Population
Conf Interval-Low Boundary = Mean - (z-value)(Standard Deviation)
Conf Interval-High Boundary = Mean + (z-value)(Standard Deviation)
Margin of Error - Population Standard Deviation Known
(z-value)(Standard Deviation)
Margin of Error - Population Standard Deviation Unknown, using the Sample’s Std Dev
(z-value)(Standard Deviation) / (square root of the sample size)
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z-value Critical Values:
1.65 90% confidence
1.96 95% confidence
2.58 99% confidence
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