PreparED Study Materials
STAT 220: Statistics in Modern Society
School: University of Rhode Island
Number of Notes and Study Guides Available: 0
Videos
Pet Phone Calls: Validating a 37% Claim with Z-test
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
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.
Testing the 123-Gallon Daily Water Claim: Fact or Fiction?
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Explore the claim that average daily water consumption is 123 gallons. Using statistical testing, we evaluate a new sample against the Old Farmer’s Almanac claim. Learn how to interpret p-values and t-scores in hypothesis testing.
Calculating Mean & Modal Class for Million-Dollar Bonuses
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Learn how to determine the mean and modal class for bonuses in millions. Understand midpoint calculations and how frequencies impact results. Gain insights into bonus distributions in the financial realm.
Calcium in Chautauqua's Rain: 1990 vs. 2010 Analysis
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
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.
Confidence Intervals for Bag Weights: A Statistical Guide
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Understand the process of determining the 94.26% confidence interval for the median weight of "80-pound" bags of water softener pellets using a standard normal table and specified formulas. Additionally, explore the steps to deduce a confidence level of 90.47%.
Cereal Box Weights: Z-Scores, Probabilities & Truth Behind Claims
Want To Learn More? To watch the entire video and ALL of the videos in the series:
full solution
Explore the intricacies of evaluating cereal box weights using Z-scores and normal distribution. By examining both individual boxes and a sample mean, understand the probabilities of achieving certain weight values. Gain insights into how statistical tools help interpret real-world product claims.





