Answer to Question #181254 in Statistics and Probability for Kathleen Narciso

Question

Find the 99th percentile of the normal curve

Answer 1

The formula below is used to compute percentiles of a normal distribution.

$$X=\mu +Z\sigma$$

where $\mu$ is the mean and $\sigma$ is the standard deviation of the variable X, and Z is the value from the standard normal distribution for the desired percentile.

For 99th percentile of the normal curve z-score is $Z=2.3263.$

The 99th percentile in a normal distribution is 2.3263 standard deviations above the mean.