Question

Are:

Answer 1

Step-by-step explanation:

a. The mean can be found using the AVERAGE() function.

x = 272.7

b. The standard deviation can be found with the STDEV() function.

s = 39.9

c. The t-score can be found with the T.INV.2T() function.  The confidence level is 0.04, and the degrees of freedom is 26.

t = 2.162

d. Find the lower and upper ends of the confidence interval.

Lower = 272.7 − 2.162 × 39.9 = 186.5

Upper = 272.7 + 2.162 × 39.9 = 358.9