A statistics pratitioner took a random sample of 30 observations from a population whose standard deviation is 15 and computed the sample mean to be 50. The 90% confidence inverval for the mean will be and .

The 90% confidence inverval for the mean will be 45.509 and 54.491

Step-by-step explanation:

Information given

represent the sample mean

population mean (variable of interest)

represent the sample standard deviation

n= 30 represent the sample size  

Confidence interval

The confidence interval for the mean is given by the following formula:

  (1)

Since the Confidence is 0.90 or 90%, the value of and , the critical value would be

Now we have everything in order to replace into formula (1):

The 90% confidence inverval for the mean will be 45.509 and 54.491

7,24

step-by-step explanation: