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the firm requires a 95% confidence interval with width 0.1033 for the proportions of residents of two story houses who own their house . what is the required sample size. assume nothing is known about the population proportion of residents who own two story houses.

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Final answer:

To determine the required sample size for a 95% confidence interval with a width of 0.1033 for the proportions of residents of two-story houses who own their house, use the formula Sample Size = (Z^2 * p * (1-p)) / E^2, where Z is the z-score corresponding to the desired confidence level, p is the worst-case proportion, and E is the desired width of the confidence interval.

Step-by-step explanation:

To determine the required sample size for a 95% confidence interval with a width of 0.1033, we need to find the minimum number needed to estimate the population proportion of residents who own two-story houses. Since nothing is known about the population proportion, we can use the worst-case scenario where the proportion is 0.5.

To calculate the required sample size, we can use the formula:

Sample Size = (Z^2 * p * (1-p)) / E^2

Z is the z-score corresponding to the desired confidence level (in this case, 95% confidence corresponds to a z-score of 1.96). p is the worst-case proportion (0.5), and E is the desired width of the confidence interval (0.1033).

Plugging in the values, we get:

Sample Size = (1.96^2 * 0.5 * (1-0.5)) / 0.1033^2

Sample Size = 384.122

Rounding up to the nearest whole number, the required sample size is 385.

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