It is known that the population variance equals 484. With a…

It is known that the population variance equals 484. With a 0.95 probability, the sample size that needs to be taken to estimate the population mean if the desired margin of error is 5 or less is ____________. Refer to the following formula and table.  σ x   =   σ n  z = x – μ σ x  Standard Error = σ n  Margin of Error = z α / 2   *   σ n  Confidence Interval = x   ±   z α / 2 * σ n n= ( z * σ m a r g i n   o f   e r r o r ) 2 z dsistribution table from 0.0 to 2.49.jpg

A random sample of 144 observations has a mean of 20, a medi…

A random sample of 144 observations has a mean of 20, a median of 21, and a mode of 22. The population standard deviation is known to equal 4.8. The 95.44% confidence interval for the population mean is 19.2 to _____________. Refer to the following formula and table. σ x   =   σ n z = x – μ σ x Standard Error = σ n Margin of Error = z α / 2   *   σ n Confidence Interval = x   ±   z α / 2 * σ n z dsistribution table from 0.0 to 2.49.jpg