A set of data has a normal distribution with a mean of 5.1 and a standard deviation of 0.9. Find the percent of data less than 4.2.

A) about 16%

B) about 34%

C) about 50%

D) about 13.5%

Respuesta :

It’s A or about 16%,

Answer: A) about 16%

Step-by-step explanation:

Given: Mean :[tex]\mu=5.1[/tex]

Standard deviation : [tex]\sigma=0.9[/tex]

We know that , the value of z is given by :-

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

For x=4.2

[tex]z=\dfrac{4.2-5.1}{0.9}=-1[/tex]

The p value = [tex]P(Z<4.2)=P(z<-1)=0.1586553\approx0.16=16\%[/tex]

Hence, about 16 % of data is less than 4.2.