Question

In: Statistics and Probability

Based on past data, it is known that about 20.5% of people smoke cigarettes. Suppose we...

  1. Based on past data, it is known that about 20.5% of people smoke cigarettes. Suppose we take a sample of 100 people currently and find that only 12% smoke cigarettes. We want to see if there is evidence that the percentage of people who smoke cigarettes is decreasing.
    1. If I wanted to control my margin of error and set it to 3% with 99% confidence, what sample size would I need to take instead of the 100?
    2. Using my original sample size of 100, what would be the 99% confidence interval for the population proportion?
    3. What are the null and alternative hypotheses?
    4. What is the critical value at 99% confidence?
    5. Calculate the test statistic (using the sample of 100).
    6. Find the p-value.
    7. What conclusion would be made here at the 99% confidence level?

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Expert Solution

orchestra answered 1 year ago
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