Edwin conducted a survey to find the percentage of people in an area who smoked regularly. He defined the label "smoking regularly" for males smoking 30 or more cigarettes in a day and for females smoking 20 or more. Out of 635 persons who took part in the survey, 71 are labeled as people who smoke regularly. What is the 90% confidence interval for this population proportion? Answer choices are rounded to the hundredths place.

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Answer:

The confidence interval for this proportion = (0.09, 0.13)

Step-by-step explanation:

Confidence Interval for Proportion =

p ± z ×√p(1 - p/n)

p = proportion = x /n

x = 71

n = 635

p = 71/635

p = 0.1118110236

p ≈ 0.1118

z score for 90% confidence interval = 1.645

Confidence Interval =

0.1118 ± 1.645 × √0.1118 (1 - 0.1118)/635

0.1118 ± 1.645 × √0.09930076/635

0.1118 ± 1.645 × √0.0001563791

0.1118 ± 1.645 × 0.0125051629

0.1118 ± 0.020570993

Confidence Interval =

0.1118 - 0.020570993

= 0.091229007

Approximately to the nearest hundredth ≈ 0.09

0.1118 + 0.020570993

= 0.132370993

Approximately to the nearest hundredth = 0.13

Therefore, the confidence interval for this proportion = (0.09, 0.13)

The 90% confidence interval for the given population proportion is (0.09,0.13) and this can be determined by using the formula of the confidence interval.

Given :

  • Edwin defined the label "smoking regularly" for males smoking 30 or more cigarettes in a day and for females smoking 20 or more.
  • Out of 635 persons who took part in the survey, 71 are labeled as people who smoke regularly.

The following steps can be used in order to determine the 90% confidence interval:

Step 1 - The formula of the confidence interval is used in order to determine the 90% confidence interval.

[tex]CI = p\pm z\sqrt{\dfrac{p(1-p)}{n}}[/tex]

Step 2 - Now, substitute the values of p, n, and z in the above expression.

[tex]CI = 0.1118\pm 1.645\sqrt{\dfrac{0.1118(1-0.1118)}{635}}[/tex]

Step 3 - Simplify the above expression.

[tex]CI = 0.1118\pm 1.645\times 0.0125051629[/tex]

[tex]CI = 0.1118\pm 0.020570993[/tex]

So, the 90% confidence interval for the given population proportion is (0.09,0.13).

For more information, refer to the link given below:

https://brainly.com/question/2396419