Question

Basic computation: z score and raw score. a normal distribution has mean = 10 and a standard deviation = 2. a) find the z score corresponding to x=12. b) find the z score corresponding to x=4. c) find the raw score corresponding to z= -2. d) find the raw score corresponding to z= -1.2

Answer 1

Solution :

mean = = 10

standard deviation = = 2

a ) x = 12

Using z-score formula,

z = x - /

z = 12 -10 / 2

z = 2 /2

z = 1

b ) x = 4

Using z-score formula,

z = x - /

z = 4 -10 / 2

z = - 6 /2

z = - 3

c ) z = - 2

Using z-score formula,

x = z * +

x = - 2 * 2 + 10

x = - 4 +10

x = 6

d ) z = - 1.2

Using z-score formula,

x = z * +

x = - 1.2 * 2 + 10

x = - 2.4 +10

x = 7.6