Find the confidence interval specified.
-30 people are selected randomly from a certain town. If their mean age is 60.5 and $\sigma$ = 4.6, find a 95% confidence interval for the true mean age, $\mu$ of everyone in the town.
A)59.42 to 61.58
B)58.85 to 62.15
C)58.28 to 62.72
D)58.86 to 62.14

Question

Find the confidence interval specified.
-30 people are selected randomly from a certain town. If their mean age is 60.5 and $\sigma$ = 4.6, find a 95% confidence interval for the true mean age, $\mu$ of everyone in the town. 
A)59.42 to 61.58
B)58.85 to 62.15
C)58.28 to 62.72
D)58.86 to 62.14

Quizplus · Accepted Answer

The 95% confidence interval is calculated using the formula: mean ± (Z * (σ/√n)). Here, the mean is 60.5, σ is 4.6, n is 30, and Z for 95% confidence is 1.96. This gives the interval 60.5 ± (1.96 * (4.6/√30)), which is approximately 58.85 to 62.15.

Find the Confidence Interval Specified σ\sigmaσ = 46, Find a 95% Confidence Interval for the True Mean

Find the Confidence Interval Specified $\sigma$ = 46, Find a 95% Confidence Interval for the True Mean