Question

A popular video game claims that the average time needed to reach level 10 Paladin is 3 hours with a standard deviation of 0.4 hours. James thinks that he and his four friends are more skilled than the average gamer because it took them an average of only 2.5 hours. Which of the following is the most restrictive level that would validate his claim?
a. 1%
b. 2.5%
c. 5%
d. 10%

Answer 1

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