A study was commissioned to find the mean weight of the residents in certain town. The study examined a random sample of 62 residents and found the mean weight to be 189 pounds with a standard deviation of 26 pounds. At the 95% confidence level, use the normal distribution/empirical rule to estimate the margin of error for the mean, rounding to the nearest tenth. (Do not write ± ).Answer:
Q. A study was commissioned to find the mean weight of the residents in certain town. The study examined a random sample of 62 residents and found the mean weight to be 189 pounds with a standard deviation of 26 pounds. At the 95% confidence level, use the normal distribution/empirical rule to estimate the margin of error for the mean, rounding to the nearest tenth. (Do not write ± ).Answer:
Identify Given Information: Identify the given information and the formula to calculate the margin of error at the 95% confidence level using the normal distribution.Given:- Sample mean (xˉ) = 189 pounds- Standard deviation (σ) = 26 pounds- Sample size (n) = 62 residents- Confidence level = 95%The formula for the margin of error (E) when using the normal distribution is:E=Z×(σ/n)Where xˉ0 is the Z-score corresponding to the desired confidence level. For a 95% confidence level, the Z-score is approximately xˉ2.
Calculate Margin of Error: Calculate the margin of error using the formula.First, calculate the standard error (SE) which is the standard deviation divided by the square root of the sample size.SE=nσSE=6226SE≈7.87426SE≈3.3Now, calculate the margin of error (E) by multiplying the Z-score by the standard error.E=Z×SEE=1.96×3.3E≈6.468Round the margin of error to the nearest tenth.E≈6.5
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