PreparED Study Materials
Notes
Videos
42.1 Web Visits: How It Stacks Up to U.S. Average
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Explore how hypothesis testing is used to compare a sample mean of Internet visits to the national average. Through calculations and statistical analysis, we determine if a sample of users' web usage significantly deviates from the average U.S. web usage.
Exit Poll Analysis: Education Funding Referendum Votes
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Explore the application of proportion z-tests in analyzing exit polling data. Understand how to determine the likelihood of sample results given a population proportion. Recognize the importance of considering non-sampling errors in interpreting exit poll outcomes.
Crunching Car Sales Data: Size, Color, and Probability Insights
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Uncover the likelihood of different car combinations by size and color from a dealer's sales data. Learn how to calculate probabilities, from the chances of a small car being black to the odds a non-small car isn't gray. An insightful look into understanding car preferences.
Chi-Square Observations: Probability of Exceeding 7.779
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Discover how to compute the likelihood of observations exceeding a certain value in a chi-square distribution with 4 degrees of freedom. Using the binomial distribution formula, evaluate the chances of at most 3 out of 15 observations surpassing the 7.779 mark. Results highlight the intricacies of data distributions.
Committee Selection: Breaking Down Probabilities
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Uncover the mathematical methods used to determine various probabilities when selecting committees. Utilize combination formulas and probabilities to evaluate different teacher-parent combinations.
Analyzing Teen Texting: Confidence Interval & Plausibility
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Discover how to calculate the 95% confidence interval for a population proportion using sample data. Through a practical example about texting habits among American teens, learn the implications of this statistical tool and how to assess plausibility.


















