contestada

At a local company, the ages of all new employees hired during the last 10 years are normally distributed. The mean age is 32 years old, with a standard deviation of 10 years. Find the percent of new employees that are at least 25 years old. Round to the nearest percent.

Respuesta :

luisejr77

Answer:

P = 76%

Step-by-step explanation:

We look for the percentage of employees who are at least 25 years old.

We know that:

μ = 32 years

[tex]\sigma = 10[/tex] years

And we want to find

[tex]P(X\geq25) [/tex]

Then we find the z-score

[tex]Z =\frac{X - \mu}{\sigma}[/tex]

So

[tex]Z = -0.7[/tex]

Then

[tex]P (X\geq25) = P(\frac{X- \mu}{\sigma}\geq\frac{25-32}{10})\\\\\P (X\geq25) = P (Z\geq -0.7)[/tex]

By symmetry of the distribution

[tex]P(Z\geq -0.7)= 1-P(Z<-0.7)[/tex]

[tex]P(Z\geq -0.7)= 1-0.242[/tex]

Looking in the normal standard tables

[tex]P(Z\geq -0.7)= 0.758[/tex]

Finally P = 76%

Otras preguntas