Question

An article published in the Washington Post claims that 45 percent of all Americans have brown eyes. A random sample of =80 college students students found 30 who had brown eyes.

Answer 1

a. -1.35

b. 0.177016

Explanation:

According to the question, following data is given

Brown eyes american percentage is 45

Random sample be 80 out of which 30 had brown eyes

Based on the above information

The computation is shown below:

a. The proportion of the sample is

`\bar p = (30)/(80)\\\\= 0.375`

The z value is

`z = \frac{\bar p - p }{\sqrt{(p(1 - p))/(n) } } \\\\\frac{0.375-0.45 }{\sqrt{(0.45(1 - 0.45))/(80) } }`

= -1.35

b Now the P value is

As z comes -1.35

So, there is a two tailed p value i.e. 0.177016