contestada

For a distribution of scores, X = 40 corresponds to a z-score of z = +1.00, and X = 28 corresponds to a z-score of z = –0.50. What are the values for the mean and standard deviation for the distribution? (Hint: Sketch a distribution and locate each of the z-score positions.)

Respuesta :

Answer

given,

X = 40         z = +1.00,

X = 28         z = -0.50

[tex]Z = \dfrac{x - \mu}{\sigma}[/tex]

[tex]1 = \dfrac{40 - \mu}{\sigma}[/tex]

[tex]\sigma =40 - \mu[/tex] ..................(1)

[tex]-0.5 = \dfrac{28 - \mu}{\sigma}[/tex]

[tex]-0.5\sigma =28 - \mu[/tex]...............(2)

from equation (1) and (2)

[tex]1.5\sigma = 12[/tex]

[tex]\sigma = 8[/tex]

from equation (1)

[tex]8 =40 - \mu[/tex]

[tex]\mu = 32[/tex]

Otras preguntas