Assume that adults have IQ scores that are normally distributed with a mean of 104.3 and a standard deviation 18.4. Find the first quartile Q,, which is the lo score separating the bottom 25% from the top 75%. (Hint: Draw a graph)The first quartie is(Type an integer or decimal rounded to one decimal place as needed)

Respuesta :

Given:

[tex]mean,\text{ }\mu=104.3\text{ and standard deviation, }\sigma=18.4.[/tex]

Required:

We need to find the first quartile Q1.

Explanation:

Consider the formula to find the first quartile Q1.

[tex]Q1=\mu-(0.675)\sigma[/tex]

[tex]Q3=\mu+(0.675)\sigma[/tex]

[tex]Substitute\text{ }\mu=104.3\text{ and }\sigma=18.4\text{ in the formula }Q1=\mu-(0.675)\sigma.[/tex]

[tex]Q1=104.3-(0.675)(18.4)[/tex]

[tex]Q1=91.88[/tex]

[tex]Q1=91.9[/tex]

Final answer:

The first quartile is 91.9.