A research team conducted a study of VARIABILITY in students' test performance. Researchers assu. that individual records are normally distributed with unknown mean and variance. They collectec sample of n = 25 test scores with summaries shown below. Sample Mean = X = 75.2 and Sample SD = S = 15 Estimate the POPULATION VARIANCE with confidence C = 0.99 • Show critical values needed • Evaluate the upper and lower confidence limits. UCL = LCL = Solution

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A: It is given that n1=20, n2=20, x1-bar=0.43, x2-bar=0.48, s1=1.27 and s2=0.91.

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A: The null and alternative hypothesis is H0:µ =175 and H1:µ>175 Here, standard deviation is 20.

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A: Given  n=11, mu=30, X1bar=31, s=2.5, alpha=0.05 Note:According to Bartleby Expert guideline, we can…

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A: Given,sample size(n)=10population standard deviation(σ)=20H0:μ=175H1:μ>175

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A: Given: n=26, σ02=0.0004 and s2=0.0005.

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A: option 1 is the best suitable option...

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A: Given info: Here, n1=15,  n2=18, x1-x2=4, and sp=4.2.

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Q: variance

A: Given: n=30 s2=0.0005 α=0.05 Set the hypothesis: H0 : σ2≤0.0004Ha : σ2>0.0004

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