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Advanced Math Topics. 9.2/9.3 Estimating the Population Mean From a Large Sample. Remember this from last chapter?. How would you find the limits of the sample means that lie in the middle 95% of the normal distribution?. .475. .475. μ x. Lower Limit. Upper Limit.
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Advanced Math Topics 9.2/9.3 Estimating the Population Mean From a Large Sample
Remember this from last chapter? How would you find the limits of the sample means that lie in the middle 95% of the normal distribution? .475 .475 μx Lower Limit Upper Limit If you did not know the mean of a population (μ), but you knew a sample mean ( x ), it would help to have a formula for μ. Rearrange the formulas above to get…
95% Confidence Interval for μ If x is known for a large sample (y > 30), and σ is the sample standard deviation, then there is a 95% chance that the population mean (μ), lies within the interval… and μ
You may want to know a different interval than 95%... Lower Boundary Upper Boundary 90% Confidence Interval 99% Confidence Interval
A sample survey of 81 movie theaters showed that the average length of the main feature film was 90 minutes with a standard deviation of 20 minutes. Find a… a) 90% confidence interval for the mean of the population. The 90% confidence interval for μ is 86.34 to 93.66 minutes. b) 95% confidence interval for the mean of the population. The 95% confidence interval for μ is 85.64 to 94.36 minutes.
From the HW P. 445 • A sample of 49 banks found that the average charge for a money order was $2.75 • for amounts up to $1000. The standard deviation was $0.25. Find a 90% confidence • interval for the average charge for a money order. The 90% confidence interval is $2.69 to $2.81.
HW P. 445 #1-8