Here we find a z-score that corresponds to a given percentile (a) Find the z-sco
ID: 3124388 • Letter: H
Question
Here we find a z-score that corresponds to a given percentile
(a) Find the z-score that marks the 85th percentile (denoted P85). That is, find the z-score that delineates the lower 85% from the upper 15% of all the z-scores.
(b) Find the z-score that marks the 25th percentile (denoted P25). That is, find the z-score that delineates the lower 25% from the upper 75% of all the z-scores.4.
Here we find the z-scores that delineate the middle portions of the standard normal distribution.
(a) Find the range of z-scores that constitute the middle 95% of all values from the others.
(b) Find the range of z-scores that constitute the middle 99% of all values from the others.
Explanation / Answer
P85 = 1.036
P25 = -0.674
Middle 95% : -1.96 to +1.96
Middle 99% : -2.5758 to +2.5758
Use the Norm.S.Inv formula on excel to get the values.
Hope this helps. Ask if you have doubts.