13% of a sample of 200 students do not like ice cream. What is the 95% confidence interval to describe the total percentage of students who do not like ice cream?

13 of a sample of 200 students do not like ice cream What is the 95 confidence interval to describe the total percentage of students who do not like ice cream class=

Respuesta :

The 95% confidence interval is (8.3%,17.7%), and the correct option is C.

------------------------------------------

In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.

[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

In which

z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].

------------------------------------------

13% of a sample of 200 students do not like ice cream.

This means that [tex]\pi = 0.13, n = 200[/tex]

------------------------------------------

95% confidence level

So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].

------------------------------------------

The lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.13 - 1.96\sqrt{\frac{0.13*0.87}{200}} = 0.083[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.13 + 1.96\sqrt{\frac{0.13*0.87}{200}} = 0.177[/tex]

------------------------------------------

As a percentage:

  • 0.083x100% = 8.3%
  • 0.177x100% = 17.7%

Thus, the 95% confidence interval is (8.3%,17.7%), and the correct option is C.

A similar problem is given at https://brainly.com/question/22223066