Question 1173270
This is a Chi Square with df=27
(n-1) s^2/ChiSq 0.025, df=27 < sigma ^2 < (n-1)s^2/ChiSq 0.975,df=27
26*27.04/43.195 < 26*27.04/14.573 Chi Square from the table
=16.28 < sigma ^2 < 48.24
That is the 95% CI of the variance
take the square root for the CI of the sd
4.03 < sigma < 6.95
or (4.03, 6.95) units minutes