Question

Mr grays quiz was normally distributed with a mean of 25 and a standard deviation of 10 find z-scores for each of the following (a) 40 (b) 27 (c) 6

Answer 1

Mean = 25 = µ
standard deviation = 10

$z = \frac{x - u}{sd}$
(a) x = 40
then z = 40-25 / 10 = -15/10 = -1.5
(b) x = 27
then z = 27-25 / 10 = 2/10 = 0.2
(c) x = 6
then z = 6-25 / 10 = -19/10 = -1.9