Miss Romero noted that the mean scores of a random sample of 15 Grade 8 students who had taken a special test was 80.5. If the standard deviation of the scores was 3.1, and the sample came from an approximately normal population, find the point and interval estimate of the population mean, using 95% confidence.

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Q: 1. Miss Romero noted that the mean scores of a random sample of 15 Grade 8 students who had taken a…

A: Since you have asked multiple questions, we will solve the first question for you. If you want any…

Q: If the mean exam score of a class was 75%, with a standard deviation of 15%,what percent of students…

A: Given,mean(μ)=0.75standard deviation(σ)=0.15

Q: Miss Romero noted that the mean scores of a random samples of 15 Grade- 8 students who had taken a…

A: Given,   Sample mean x¯ = 80.5standard deviation σ = 3Sample size n = 8

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Q: The test scores for a very large statistics class have a bell-shaped distribution with a mean of 72…

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A: Given data, µ = 52  σ= 9 n=27 sampling error=?

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Q: a data set has a mean of 210 and a standard deviation of 40, what is the z- Score for a ralue of140…

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Q: A statistics professor announces that 15% of the grades he gives are As.  The results of the final…

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