PreparED Study Materials
ST 421: ST 421
School: North Carolina State University
Number of Notes and Study Guides Available: 2
Notes
Videos
Analyzing Voter Demographics: Independence & Exclusivity
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Analyze the relationships between different political affiliations and age groups. Determine whether certain events are independent, mutually exclusive, or neither, based on the provided probabilities. The findings offer a nuanced understanding of voter demographics and their interdependencies.
Evaluating Expressions Using a Set of Scores
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Discover the methodology behind evaluating various mathematical expressions using a given set of scores. By interpreting and applying summation notation, learn how to compute the desired results from a set of numbers. Key conclusions showcase the step-by-step calculations and their significance.
Calculating Permutations: 720 Ways to Arrange 6 Objects
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Discover the principles of permutations with 6 distinct objects. Learn the ins and outs of factorial calculation and its application to combinatorics. Grasp the method to find the number of unique arrangements for any set of items.
Two-Sample T-Test: Analyzing Control vs. Supplemented Groups
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Explore the steps to conduct a two-sample t-test using a control and supplemented group. Through hypothesis testing, standard deviation, and P-value interpretation, we analyze the means of both groups to determine statistical differences.
Computers in Schools: Probabilities & Distributions
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Assess the distribution of computers across schools using statistical methods. Determine the probability of a randomly selected school having a specific number of computers. From fewer than 50 to more than 100 computers, derive insightful conclusions about school infrastructures.
011 Car Colors in North America: Trends & Visual Insights
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Discover the trends in car colors for North America in 2011. Break down the percentage distribution of various shades, from dominating whites to the less frequent greens. Understand the best visual techniques to represent this data, weighing the pros and cons of graphs.

















