Posted by Glenn D on .
Find the 95% confidence interval for the difference between two means based on this information about two samples. Assume independent samples from normal populations. (Use conservative degrees of freedom.) (Give your answers correct to two decimal places.)
Sample Number Mean Std. Dev.
1 27 39 21
2 16 26 35
Lower Limit 7.02 .
Upper Limit 33.02 .

math check 
Kuai,
Those answer are wrong.
Conservative degrees of Freedom mean that you could use small number. Df = 15
T table