The population mean annual salary for environmental compliance specialists is about ​$60 comma 500. A random sample of 32 specialists is drawn from this population. What is the probability that the mean salary of the sample is less than ​$57 comma 500​? Assume sigmaequals​$6 comma 400.

Respuesta :

Answer:

0.004 is the probability that the mean salary of the sample is less than ​$57,500.

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = $60,500

Standard Deviation, σ = $6,400

Sample size, n  = 32

Formula:

[tex]z_{score} = \displaystyle\frac{x-\mu}{\sigma}[/tex]

Standard error due to sampling =

[tex]=\dfrac{\sigma}{\sqrt{n}} = \dfrac{6400}{\sqrt{32}} =1131.37[/tex]

P(mean salary of the sample is less than $57,500)

[tex]P( x < 57500) = P( z < \displaystyle\frac{57500 - 60500}{1131.37}) = P(z <-2.6516)[/tex]

Calculation the value from standard normal z table, we have,  

[tex]P(x < 57500) = 0.004[/tex]

0.004 is the probability that the mean salary of the sample is less than ​$57,500.