Use the confidence interval to find the margin of error and the sample mean. (0.142,0.300) The margin of error is The sample mean is

Use the confidence interval to find the estimated margin of error. Then find the sample mean.   A store manager reports a confidence interval of (42.6,78.2)when estimating the mean price​ (in dollars) for the population of textbooks. The estimated margin of error is ​(Type an integer or a​ decimal.) The sample mean is ​(Type an integer or a​ decimal.)

Social Networking Sites A recent survey of social networking sites has a mean of million visitors for a specific month. The standard deviation was million. Find the confidence interval of the true mean. Assume the variable is normally distributed. Round your answers to at least two decimal places.Social Networking Sites A recent survey of 6 social networking sites has a mean of 13 million visitors for a specific month. The standard deviation was 3.2 million. Find the 90% confidence interval of the true mean. Assume the variable is normally distributed. Round your answers to at least two decimal places.

Private Four-Year Colleges From the data in CollegeScores4yr we know that about 62% of four-year colleges in the US are private institutions. Suppose that we select samples of n = 75 schools at a time from the population of all four-year colleges and find the proportion of private schools in each sample. (a) Consider the distribution of these sample proportions when n = 75 and p = 0.62. What is its form? Center = i Standard error = (round to three decimal places) (b) What proportion of these samples will have less than 50% private schools? Round to three decimal places. i

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Use the confidence interval to find the estimated margin of error. Then find the sample mean.   A biologist reports a confidence interval of (3.0,4.4) when estimating the mean height​ (in centimeters) of a sample of seedlings.       Question content area bottom Part 1 The estimated margin of error is enter your response here   .

Construct a confidence interval for the population mean.  Assume that the population has a normal distribution.  n= 30, x bar = 84.6, s=10.5, 90% confidence.

The mean score for Scrabble players at the neighborhood center is m = 215 points. The players read a book that claims it can raise scores significantly.  After reading the book, a team of 25 players obtains a score of M = 218 points, with s= 25.  Do the data indicate that reading the book leads to increases in the players’ scores?  Test with a = .05 Calculate and evaluate Cohen’s d and r2. What decision can you make and what does it indicate? What type of error could you be making and what would that mean? Report your results with an APA-style phrase.