Question

For a sample of n = 30 scores, X = 45 corresponds to z = 1.50 and X = 40 corresponds to z = +1.00. What are the values for the sample mean and standard deviation?

Answer 1

Answer:

30

Step-by-step explanation:

Here, it is given that the Z – score corresponding to the score X = 45 is 1.5 and the Z – score corresponding to the score X = 40 is...

Z = $\frac{X - M}{S}$

So:

1/ 1.5 = $\frac{45 - M}{S}$ and 1 = $\frac{40 -M}{S}$ . solve the both equations, we found out:

<=> S = 10

=> M = 30

Hence, mean is:

M = 45 -1.5S = 45 - 1.5 (10) = 30