Survey on Politics In a study, 68% of 903 randomly selected adults said they believe the Republicans favor the rich. If the margin of error was 2 percentage points, what was the confidence level used for the proportion? Round the intermediate calculations to four decimal places, round the z value to two decimal places, and round the final answer to the nearest whole number. The confidence level is

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**Survey on Politics**

In a study, 68% of 903 randomly selected adults said they believe the Republicans favor the rich. If the margin of error was 2 percentage points, what was the confidence level used for the proportion? 

Round the intermediate calculations to four decimal places, round the z value to two decimal places, and round the final answer to the nearest whole number.

[Input Box]
The confidence level is [   ]%.

---

**Explanation of Calculations:**

To find the confidence level, you need to calculate the z-score corresponding to the given margin of error and sample proportion. Then, translate the z-score to a percentage representing the confidence level.

1. **Sample Proportion (p-hat):** 0.68
2. **Sample Size (n):** 903
3. **Margin of Error (E):** 0.02 (2 percentage points)

**Formula for Margin of Error:**
\[ E = z \times \sqrt{\frac{p(1-p)}{n}} \]

Where:
- \( p \) is the sample proportion (0.68)
- \( n \) is the sample size (903)

**Steps:**
1. Calculate the standard error (SE) using \( \sqrt{\frac{p(1-p)}{n}} \).
2. Solve for z using the margin of error formula.
3. Convert the z-value to a confidence level percentage.

**Rounding Instructions:**
- Intermediate calculations to four decimal places.
- z value to two decimal places.
- Final answer to the nearest whole number.

Remember to use z-tables or statistical software to convert the computed z-value to its corresponding confidence level.
Transcribed Image Text:**Survey on Politics** In a study, 68% of 903 randomly selected adults said they believe the Republicans favor the rich. If the margin of error was 2 percentage points, what was the confidence level used for the proportion? Round the intermediate calculations to four decimal places, round the z value to two decimal places, and round the final answer to the nearest whole number. [Input Box] The confidence level is [ ]%. --- **Explanation of Calculations:** To find the confidence level, you need to calculate the z-score corresponding to the given margin of error and sample proportion. Then, translate the z-score to a percentage representing the confidence level. 1. **Sample Proportion (p-hat):** 0.68 2. **Sample Size (n):** 903 3. **Margin of Error (E):** 0.02 (2 percentage points) **Formula for Margin of Error:** \[ E = z \times \sqrt{\frac{p(1-p)}{n}} \] Where: - \( p \) is the sample proportion (0.68) - \( n \) is the sample size (903) **Steps:** 1. Calculate the standard error (SE) using \( \sqrt{\frac{p(1-p)}{n}} \). 2. Solve for z using the margin of error formula. 3. Convert the z-value to a confidence level percentage. **Rounding Instructions:** - Intermediate calculations to four decimal places. - z value to two decimal places. - Final answer to the nearest whole number. Remember to use z-tables or statistical software to convert the computed z-value to its corresponding confidence level.
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