Question 1109276
Two way test to see if any different (one may argue in favor of a one way test, but this question sounds more like hoping it was better rather than knowing a priori it would be.)
usual assumptions or normality
z=test with critical value |z|>1.96
z=(xbar-mean)/sigma/sqrt(n)
z=24*sqrt(72)/100, inverting the denominator to multiply
z=2.036, the test statisitic
This has a p-value of 0.041, and is considered significant at the 0.05 level and supports the principal's claim.