PreparED Study Materials
Notes
Videos
Calcium in Chautauqua's Rain: 1990 vs. 2010 Analysis
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Explore the calcium concentration in Chautauqua's rainwater from 2010, comparing it to 1990 levels. Using statistical tests, examine normal distribution and determine significant changes. The results provide insights into environmental shifts over two decades.
Testing the Claim: Is Soft Drink Consumption Really 52 Gallons?
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Discover the process of using a one-sample t-test to validate a claim about average soft drink consumption. By calculating the test statistic and analyzing the corresponding P-value, we determine the validity of the researcher's assertion.
Calculating Confidence Interval for Educational TV Viewership
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Learn how to determine a 90% confidence interval for the proportion of people who watch educational television based on a survey. Understand how to utilize the z-score and interpret results, guiding decisions for a television company's publicity efforts.
Choosing Samples: The Math of Online Freebies
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Discover the mathematical principles behind choosing free samples in online shopping scenarios. Understand combinations, how to calculate them, and see real-world examples of selecting multiple items.
Pet Phone Calls: Validating a 37% Claim with Z-test
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Explore a claim from the American Animal Hospital Association that 37% of pet owners communicate with their pets over the phone. Through hypothesis testing and a z-test, evaluate a skeptical veterinarian's doubts. Conclusions shed light on pet owners' unique communication habits.
Car Theft Rates: Does Your Car Type Influence Risk?
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Explore the relationship between specific car types and their theft rates. This video assesses correlations between car models like the Honda Accord, Toyota Camry, and others, emphasizing the difference between correlation and causation.



















