How to Find Probabilities for Z with the ZTable
You can use the Ztable to find a full set of “lessthan” probabilities for a wide range of zvalues. To use the Ztable to find probabilities for a statistical sample with a standard normal (Z) distribution, do the following:

Go to the row that represents the ones digit and the first digit after the decimal point (the tenths digit) of your zvalue.

Go to the column that represents the second digit after the decimal point (the hundredths digit) of your zvalue.

Intersect the row and column from Steps 1 and 2.
This result represents p(Z < z), the probability that the random variable Z is less than the value z (also known as the percentage of zvalues that are less than the given z value ).
For example, suppose you want to find p(Z < 2.13). Using the Ztable below, find the row for 2.1 and the column for 0.03. Intersect that row and column to find the probability: 0.9834. Therefore p(Z < 2.13) = 0.9834.
Noting that the total area under any normal curve (including the standardized normal curve) is 1, it follows that p(Z < 2.13) + p(Z > 2.13) =1. Therefore, p(Z > 2.13) = 1 – p(Z < 2.13) which equals 1 – 0.9834 which equals 0.0166.
Suppose you want to look for p(Z < –2.13). You find the row for –2.1 and the column for 0.03. Intersect the row and column and you find 0.0166; that means p(Z < –2.13)=0.0166. Observe that this happens to equal p(Z>+2.13).The reason for this is ‘ because the normal distribution is symmetric. So the tail of the curve below –2.13 representing p(Z < –2.13) looks exactly like the tail above 2.13 representing p(Z > +2.13).