University officials say that at least 70% of the voting student population supports a fee increase. If the 95% confidence interval estimating the proportion of students supporting the fee increase is [0.75,0.85],what conclusion can be drawn?
A)Seventy percent is not in the interval,so another sample is needed.
B)Seventy percent is not in the interval,so assume it will not be supported.
C)The interval estimate is above 70%,so infer that it will be supported.
D)Since this was not based on the population,no conclusion can be drawn.

Question

Quizplus · Accepted Answer

The interval estimate is above 70%, so it can be inferred that the fee increase will be supported by at least 70% of the student population. Since the 95% confidence interval is relatively narrow and the lower bound is still relatively high, we can be 95% confident that the true proportion of students supporting the fee increase is greater than 0.75, which is higher than the 70% threshold. Therefore, we can draw the conclusion that the fee increase is likely to be supported by a majority of students.

University Officials Say That at Least 70% of the Voting