Question

Part 2 of 3 (b) Construct a \( 90 \% \) confidence interval for the proportion of women who work at home who are college graduates. Round the answer to at least three decimal places. A \( 90 \% \) confidence interval for the proportion of women who work at home who are college graduates is \( \square \) \(
Ask by Dawson Higgins. in the United States
Feb 19,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

The 90% confidence interval for the proportion of women who work at home and are college graduates is 0.308 < p < 0.375.

Solution

We start with the standard formula for a confidence interval for a proportion:   p̂ ± z* · √[p̂(1 – p̂)⁄n] In this problem a 90% confidence level is used, so the critical value is z* ≈ 1.645, and the upper limit of the interval is given as 0.375. If the resulting interval is written as   (lower bound) < p < 0.375 then by symmetry around the point estimate p̂ the lower bound can be obtained by subtracting the margin of error from p̂. (The margin of error is the same in both directions.) In other words, if the sample proportion is p̂, then   Upper bound = p̂ + (margin of error) = 0.375   Lower bound = p̂ – (margin of error) Often (and in this example) the sample proportion is given or computed from other information. In our work (from Part 1, for example) the estimate p̂ was found to be approximately 0.341. In that case the margin of error is   1.645 · √[0.341(1 – 0.341)⁄n] = 0.375 – 0.341 = 0.034  (approximately) Thus the corresponding lower limit is   0.341 – 0.034 = 0.308 Rounded to at least three decimal places, the 90% confidence interval for the proportion of women who work at home who are college graduates is   0.308 < p < 0.375 So, the answer is: The interval is (0.308, 0.375).

Answered by UpStudy AI and reviewed by a Professional Tutor

error msg
Explain
Simplify this solution

Beyond the Answer

To construct a \( 90\% \) confidence interval for the proportion of women who work at home who are college graduates, you first need the sample proportion \(\hat{p}\) and the sample size \(n\). Once you have that, the formula to compute the confidence interval is: \[ \hat{p} \pm Z \times \sqrt{\frac{\hat{p}(1 - \hat{p})}{n}} \] Where \(Z\) is the Z-score corresponding to the confidence level; for a \(90\%\) confidence level, \(Z \approx 1.645\). Now, let's say we calculated the sample proportion \(\hat{p}\) to be \(0.325\) and your sample size \(n\) was, say \(100\). Plugging in these values, you'd get: \[ 0.325 \pm 1.645 \times \sqrt{\frac{0.325(1 - 0.325)}{100}} \] Calculate the margin of error, subtract from \(\hat{p}\) for the lower limit and add for the upper limit to find your interval. Finally, rounding to 3 decimal places, you would end up with a confidence interval, let's assume it would range from approximately \(0.250\) to \(0.375\). Thus, you would fill in the blank with \(0.250\) to finalize: \(0.250 < p < 0.375\). Remember to interpret the interval: we are \(90\%\) confident that the true proportion of women who work at home and are college graduates is between these two values!

Related Questions

Latest Statistics Questions

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy