4.5 - Confidence Intervals
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Practice Questions
Test your understanding with targeted questions
What is a confidence interval?
💡 Hint: Think about what it means to estimate a parameter.
What is the purpose of the population standard deviation in the confidence interval formula?
💡 Hint: Consider how variability impacts your estimates.
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Interactive Quizzes
Quick quizzes to reinforce your learning
What does a 95% confidence interval imply?
💡 Hint: Think about how confidence intervals reflect sampling behavior.
True or False: A wider confidence interval indicates greater precision in estimating the population parameter.
💡 Hint: Consider the relationship between width and certainty.
1 more question available
Challenge Problems
Push your limits with advanced challenges
A researcher claims the average height of a species of tree is 15 feet. They collect a sample of 50 trees, which has a mean height of 14.5 feet and a standard deviation of 2 feet. Calculate the 95% confidence interval and discuss its implications.
💡 Hint: Use the provided formula and keep the critical z-value in mind for your calculations.
If a sample of 30 students has a mean score of 85 on a final exam with a standard deviation of 5, construct a 99% confidence interval. What does this say about the strength of your estimate?
💡 Hint: Remember to find the appropriate z-value for the 99% confidence level.
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