Question 1121477
the interval is +/-t0.975, df=11*s/sqrt (n)
2.201*10/sqrt(12=6.35
interval is (108.7, 121.4)
 Please help: Both of your answers are incorrect.​ First, identify the degrees of freedom n minus one.
11 DF
LEVEL OF CONFIDENCE IS 95%,
T-VALUE 0.975, DF=11 IS 2.201.  AS THE QUESTION IS STATED, THERE IS NO CRITICAL VALUE, BECAUSE THIS IS NOT HYPOTHESIS TESTING
THE MARGIN OF ERROR IS AS GIVEN.

This is for a mean (x bar) =115, s=10 and n=12.