In a random sample of 400 registered votes, 120 indicated they plan to vote for a candidate for President. Determine a 95% confidence interval for the proportion. Take z score of 1.96 at 95% confidence level
Added by Victor V.
Step 1
- The sample size (n) is 400. - The number of voters planning to vote for the candidate is 120. - The sample proportion (p̂) is calculated as: \[ p̂ = \frac{x}{n} = \frac{120}{400} = 0.30 \] Show more…
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