Paragraph Environmental engineers are using data collected by weather data cente
ID: 3363587 • Letter: P
Question
Paragraph Environmental engineers are using data collected by weather data centers to learn how dimate affects the sea ice. Of 518 ice melt ponds studied in a certain region, 103 were classified as having first-year ice The researchers estimated that about 20% of melt ponds in the region have first-year C Estimate, with 90% confidence, the percentage of all ice melt ponds in the region that have first year ice. Give a practical interpretation of the results IF Construct a 90% confidence interval around the sample proportion of ice melt ponds with first-year ice. Round to four decimal places as needed. Interpret the confidence interval practically. Choose the correct answer below A One can be 90% confident the true proportion of ice melt ponds in the region with first-year ice lies at the mean of the above interval, rather than at 20%. B One can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is within the above interval, though it is probably not 20%. C. Since 20% is not in the interval, one can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is not 20%. D One can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is within the above interval, and there is a 90% chance it is 20%. Since 20% s in the interval one can be 90% confident the true proportion of ice melt ponds in the region with first-year ice is 20Explanation / Answer
Given that ponds with first year ice i.e. p = 20% = 0.2
sample size = 518 and sample proportion = 103/518 = 0.1988
90% Confidence interval = (sample proportion - p)+-Z0.05 ((p(1-p)/n)0.5
= (0.1988) +- 1.6449 ((0.1988)(0.8012)/518)0.5
90% CI = (0.17, 0.228)
Answer is option (e) i.e. since 20% in the interval one can be 90% confident the true proportion of ice melt ponds in the region with first year ice is 20%
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.