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Multiple choice, please help ASAP

suppose a study estimated that 78% of the residents of a town (with an error range of ±8 percentage points at 95% confidence) favor expanding the park and recreation department. which of the following percentages of the town's residents may favor expanding the park and recreation department?


A. 62%


B. 52%


C. 92%


D. 72%

User Morrison
by
8.2k points

2 Answers

5 votes

Answer: 72% - Apex

Explanation:

User Javros
by
7.8k points
5 votes

Answer: D. 72%

Explanation:

The confidence interval for proportion is given by :-


p\ \pm E, where E is the margin of error.

Given : Sample size :
n=1000

The proportion of the residents of a town : p=0.78

Margin of error :
E=0.08

Significance level :
1-0.95=0.05

Critical value :
z_(\alpha/2)=1.96

Now, the 95% confidence Interval for the proportion of residents of a town will be :-


0.78\ \pm 0.08=(0.7,\ 0.86)

Thus , the

95% confidence Interval for the percentage of residents of a town will be (70%, 86%)

From all the given options only 72 % lies in the confidence interval.

Hence, 72% of the town's residents may favor expanding the park and recreation department

User Daniel LeCheminant
by
8.6k points
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