27.2k views
5 votes
If n=540 and p=0.85, construct a 95% confidence interval.

User Shevaun
by
7.9k points

1 Answer

2 votes

Final answer:

To construct a 95% confidence interval with n = 540 and p = 0.85, you calculate the margin of error using the critical value for 95% confidence, then add and subtract this margin from the sample proportion to find the lower and upper bounds of the interval.

Step-by-step explanation:

When constructing a 95% confidence interval given that n = 540 and p = 0.85, we need to calculate the margin of error and then add and subtract that margin from the sample proportion p to get the interval. To find the margin of error (EBP), we use the formula involving the critical value (Z) for the 95% confidence level, the sample proportion (p), and the sample size (n). With the TI-83, 83+, or 84+ calculator, you would input the given values for 'n' and 'p' and set the C-Level to .95 to calculate the interval.

To find the critical value Z for a 95% confidence interval, you can use the calculator function 'invNorm(0.975, 0, 1)' or look up 1.96 in the Z-table as Z0.025. Next, calculate p' (sample proportion) and q' (1 - p'), then compute EBP using the formula Z \( \sqrt{ \frac{p'(1-p')}{n} } \). The confidence interval is then p' \( \pm \) EBP.

User Manoi
by
8.0k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.