Question

The distribution of certain test scores is a nonstandard normal distribution with a mean of 50 and a standard deviation of 6. What are the values of the mean and standard deviation after all test scores have been standardized by converting them to ​z-scores using z?

Answer 1

Mean value is 0 and standard deviation is 1 after all test scores have been standardized by converting them to ​z-scores using z

Explanation:

In a standard normal distribution (also called as Gaussian distribution) all values of the sample can be projected to a normal distribution with mean 0 and standard deviation 1 using their z-scores.

z-score of a value X can be calculated as follows:

z=
`(X-50)/(6)` where

• 50 is the mean of the test scores
• 6 is the standard deviation of test scores