
Jon S. answered 03/17/21
Patient and Knowledgeable Math and English Tutor
Compute z = (13.49 - 13.41)/0.12 = 0.67
13.49 is only 0.67 standard deviations above mean, so not unusual.
minimum usual value would be 2 standard deviations below the mean of 13.41 - 2*0.12 = 13.17.