In a certain normal distribution of scores, the mean is 30 and the standard deviation is 3. find the z-score corresponding to a score of 23.

-2.333

Step-by-step explanation:

In a certain normal distribution of scores, the mean is 30 and the standard deviation is 3. Find the z-score corresponding to a score of 23.

The z-score corresponding to an observed value in a normal distribution is calculated as;

z-score = (observed value - mean)/(standard deviation)

Our observed score is 23, the mean is 30, and the standard deviation is 3. The z-score will thus be;

z-score = ( 23 - 30)/( 3)

z-score = -2.333

- 2.333

Step-by-step explanation:

The formulae to apply here is;

z= (x-μ) / δwhere x is the score, μ is the mean and δ is the standard deviation

Given x=23, μ=30 and δ= 3

z= (23-30) / 3 z= - 7/3 z=  -2.333

7.25

step-by-step explanation:

we know that 7 equals to 7.0. we also know that 1/4=0.25. so we can add the two together and we get 7.25