Construct the confidence interval for the population mean mu. c = 0.90, x = 16.9, s = 9.0, and n = 45. A 90% confidence interval for mu is:.

The  90%  confidence interval for population mean is  

Step-by-step explanation:

From the question we are told that

   The sample mean is  

    The confidence level is  

     The sample size is  

     The standard deviation

Now given that the confidence level is  0.90 the  level of significance is mathematically evaluated as

Next we obtain the critical value of    from the standardized normal distribution table. The values is  

The  reason we are obtaining critical values for  instead of  that of    is because  represents the area under the normal curve where the confidence level 1 - (90%)  did not cover which include both the left and right tail while  is just considering the area of one tail which is what we required calculate the margin of error

  Generally the margin of error is mathematically evaluated as

substituting values

The  90%  confidence level interval is mathematically represented as

substituting values