Netta-schools. net Doorman 11-3: Practice Buddy: Independent Practice; Problem Solving
11.3.14-5
Question Help
Use the line plot to answer 4-5.
4. What is the difference in height between the shortest and tallest action figures?
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5. Mark says 4 inches is the most common height he measured. Is he correct? Explain.
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Arandom sample of n = 25 observations is taken from a n(µ, σ ) population. a 95% confidence interval for µ was calculated to be (42.16, 57.84). the researcher feels that this interval is too wide. you want to reduce the interval to a width at most 12 units. a) for a confidence level of 95%, calculate the smallest sample size needed. b) for a sample size fixed at n = 25, calculate the largest confidence level 100(1 − α)% needed.