The tables of the standard normal distribution contain only positive values of z . This is because
A) the distribution is symmetric.
B) z can take on only positive values.
C) we aren't interested in negative values of z .
D) probabilities can never be negative.

Question

Quizplus · Accepted Answer

The standard normal distribution is symmetric around its mean of 0. Therefore, the negative values of z will have the same probabilities as their corresponding positive values. This is why the tables only contain positive values of z.

The Tables of the Standard Normal Distribution Contain Only Positive