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A researcher gathers a sample of n=48 people to try a new type of therapy and...

A researcher gathers a sample of n=48 people to try a new type of therapy and to compare the sample to the population mean of m=28. The sample means for depression after treatment was =22 with a standard deviation of s=4. Using this information, what is the mean for the distribution of sample means used for this study? Round your answer to 2 decimal places if appropriate.

Math   Statistics-And-Probability   
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Answer #1

Note that,

If random samples of a given size are taken from a population of values for a quantitative variable, where the population mean is μ (mu) and the population standard deviation is σ (sigma) then the mean of all sample means (x-bars) is population mean μ (mu).

Here population mean is . Therefore, mean of sample means is  .

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