Question

Find the z-score that marks the 60^th percentile (denoted P₆₀). That is, find the z-score that delineates the lower 60% from the upper 40% of all the z-scores. Enter your answer to 2 or 3 decimal places.

Answer 1

We want to find, the z-score that marks the 60th percentile.

That is to find, the z-score such that, P(Z < z0) = 0.60

Using standard normal z-table we get, z-score corresponding probability of 0.60 is, z0 = 0.25

=> P(Z < 0.25) = 0.60

Therefore, required z-score = 0.25

Note : using Excel also we find this z-score as follows :

Excel Command : =NORMSINV (0.60) = 0.253