SOLUTION: In a poll of 125 randomly selected U.S. adults, 65 said they favored a new proposition. Based on this poll, compute a 95% confidence interval for the proportion of all U.S. adults

Question 1159648: In a poll of 125 randomly selected U.S. adults, 65 said they favored a new proposition. Based on this poll, compute a 95% confidence interval for the proportion of all U.S. adults in favor of the proposition (at the time of the poll).
Carry your intermediate computations to at least three decimal places. Round your answers to two decimal places.
What is the lower limit of the 95% confidence interval?

What is the upper limit of the 95% confidence interval?
Answer by Shin123(626) (Show Source): You can put this solution on YOUR website!
The Z value for a 95% confidence interval is 1.960. The standard error is , which is 0.045 rounded to three decimal places. The true proportion of all U.S. adults in favor of the proposition is 0.52+/-(1.960*0.045),which is 0.520+/-0.088. The lower bound is and the upper bound is . Click here for a calculator if you have more problems like this.
RELATED QUESTIONS
In a poll of 200 randomly selected U.S. adults, 104 said they favored a new proposition.... (answered by stanbon)

1. In a Gallup poll of 557 randomly selected adults, 284 said that they were underpaid.... (answered by stanbon)

In a Gallup poll of 557 randomly selected adults, 284 said that they were underpaid.... (answered by stanbon)

A poll was done where 450 adults were randomly surveyed. 35 % said they were working... (answered by Boreal)

In a Gallup poll, 2400 randomly selected adults were surveyed and 39% of them said that... (answered by Boreal)

in a recent poll 70% of the surveyed said that they will not go away on vacation this... (answered by ewatrrr)

A poll was done where 450 adults were randomly surveyed. 35 % said they were working... (answered by Boreal)

In a Gallup-type poll, 1080 randomly selected adults were surveyed and 28% of them said... (answered by ewatrrr)

An opinion poll was conducted among a group of registered voters in a certain state... (answered by richwmiller)