For the answer to the question above, first, we must calculate the standard error. The standard error is standard deviation divided by the square root of the sample. In this case, it is equal to 0.178. The z-score has defined the distance from the sample to the population mean in units of standard error.
z = (3 – 2.5)/0.178 = 2.81
at this z-score, the probability is 0.9974 or
if rounded off it is 1%
I hope my answer helped
