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a distribution is normal with mu= 12.0 and sigma= 3.0. if i select one individual at random what is the probability that said individual is between 9.2 and 17.6

Respuesta :

Answer:

the probability between 9.2 and 17.6 is, 0.79237.

Step-by-step explanation:  

It is given that distribution is normal.Also given the value of  [tex]\mu = 12[/tex]

and [tex]\sigma = 3[/tex] .

Use : [tex]z = \frac{x-\mu}{\sigma}[/tex]

Now,  

Calculate First [tex]P(X>9.2)[/tex]

then we put the value of x =9.2 in the z transform,i.e, [tex]z = \frac{x-\mu}{\sigma}[/tex]

[tex]z = \frac{9.2-12}{3}= -0.933333333[/tex]  

Using the standard Normal table of N(0,1); we get

⇒ [tex]P(X>9.2) = 0.17619[/tex]

Similarly, for [tex]P(X<17.6)[/tex]

put the value of x =17.6 in the z-transform we get;

[tex]z = \frac{17.6-12}{3}=1.86666667[/tex]

By the Normal Table N(0,1); we get

⇒   [tex]P(X<17.6) = 0.96856[/tex]

Then, the probability between 9.2 and 17.6 i.e,

[tex]P(9.2<X<17.6) = 0.96856 - 0.17619=0.79237[/tex]