A random sample of 28 fields of spring wheat has a mean yield of 44.7 bushels per acre and standard deviation of 6.96 bushels per acre. Determine the 95% confidence interval for the true mean yield. Assume the population is approximately normal. Step 1 of 2 : Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places

And the confidence interval would be between 42.001 and 47.399

Step-by-step explanation:

Information given

represent the sample mean for the sample  

population mean

s=6.96 represent the sample standard deviation

n=28 represent the sample size  

Confidence interval

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

  (1)

The degrees of freedom are given by:

The Confidence interval is 0.95 or 95%, the significance is and ,the critical value for this case would be

And replacing we got:

And the confidence interval would be between 42.001 and 47.399