To calculate the margin of error for the population mean estimate, we can use the following formula:
\[ \text{Margin of Error} = z \left( \frac{\sigma}{\sqrt{n}} \right) \]
where:
- \( z \) is the z-score corresponding to the desired confidence level,
- \( \sigma \) is the population standard deviation,
- \( n \) is the sample size.
-
Determine the z-score for a 98% confidence level: The z-score for a 98% confidence level can generally be found from z-tables or standard normal distribution charts. For 98% confidence, the z-score is approximately 2.33.
-
Use the given values:
- \( n = 1503 \)
- \( \sigma = 0.5 \)
-
Calculate the margin of error:
\[ \text{Margin of Error} = 2.33 \left( \frac{0.5}{\sqrt{1503}} \right) \]
Calculating the sample size's square root:
\[ \sqrt{1503} \approx 38.73 \]
Now substituting that into the equation:
\[ \text{Margin of Error} = 2.33 \left( \frac{0.5}{38.73} \right) \approx 2.33 \left( 0.01292 \right) \approx 0.0301 \]
Rounding this results in approximately 0.03.
Final Answer: 0.03