Please help me, I am very confused with the question below.

So, now that we have been discussing the question for a few days, you can see that if you use the "probability < 5%" criterion the answer is "unusual", whereas if you use the "more that two standard deviations" criterion the answer is "not unusual". Who wants to tells us why this is not really a contradiction? HINT: In a normal distribution, the roughly 5% of unusual events are split into TWO tails (left and right).

This was the original question:

Assume that a population is normally distributed with a mean of 100 and a standard deviation of 15. Would it be unusual for the mean of a sample of 3 to be 115 or more? Why or why not?