Determine the point estimate of the population mean and marg

Determine the point estimate of the population mean and margin of error for the confidence interval.

Lower bound is 22, upper bound is 28

The point estimate of the population mean is ___

The margin of error for the confidence interval is ___

Solution

Given Lower bound is 22, that is, sample mean - Marginal Error = 22 ....(1)

and   Upper bound is 28, that is, sample mean + Marginal Error = 28 .....(2)

Add (1) and (2) then 2(Sample Mean) = 50, therefore, sample mean = 50/2 = 25. It is the point estimate of Population mean. i.e. estiamated population mean = 25.

From (1), 25 - Marginal Error = 22, therefore, Marginal Error = 25 - 22 = 3.