SOLUTION: a) A consumer agency that proposes that lawyers’ rates in a particular city are too high wanted to estimate the mean hourly rate for all lawyers in that city. A sample of 70 lawye

Algebra.Com
Question 1120011: a) A consumer agency that proposes that lawyers’ rates in a particular city are too high wanted to
estimate the mean hourly rate for all lawyers in that city. A sample of 70 lawyers taken from the
city showed that the mean hourly rate charged by them is $420. The population standard deviation
of hourly charges for all lawyers is $110.
i. Construct a 95% confidence interval for the mean hourly charges for all lawyers in the City.

ii. Briefly interpret the interval constructed in a) (i) above.

Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
The half interval is z*sigma/sqrt (n)
This is 1.96*110/sqrt(70) for a 95% CI
=$25.77
interval is $420+/- $25.77
($394.23, $445.77)
This means while we don't know the exact mean, short of surveying every lawyer, we can be very confident that the true value lies in this interval. We are using confidence, because the true value either DOES or DOES NOT lie in the interval, and that is not a useful probability statement.

RELATED QUESTIONS

1.A sample of 36 students are drawn from the NUST student population, and their body... (answered by greenestamps)
The breaking strengths of cables produced by a certain company are approximately normally (answered by stanbon)
The breaking strengths of cables produced by a certain company are approximately... (answered by stanbon)
1.Due to the sharp increase in the prices of urban properties over the last five years,... (answered by greenestamps)
a committee of five people is to be formed from six lawyers and seven teachers. find the... (answered by stanbon,Theo)
Can you please help me solve this problem? A sample of 200 policemen showed that 65% (answered by stanbon)
A food safety guideline is that the mercury in fish should be below 1 part per million​ (answered by Boreal)
A food safety guideline is that the mercury in fish should be below 1 part per million​ (answered by Glaviolette)
A food safety guideline is that the mercury in fish should be below 1 part per million​ (answered by Boreal)