Question

In: Statistics and Probability

Noise levels at various road construction sites were measured in decibels. The mean the noise levels...

Noise levels at various road construction sites were measured in decibels. The mean

the noise levels in a sample of 64 construction sites was 85 decibels. The

population standard deviation is 10 decibels. Find the 95% confidence interval for

the true mean noise level at road construction sites.

Expert Solution

Let noise level at a road construction site in decibels be denoted by X.

Assumption :- X ~ N(,)

Let the mean of the sample of size 64 be denoted as .

So the 95% confidence interval for the true mean noise level at road construction sites is :-

(82.55 decibels , 87.45 decibels).

orchestra answered 1 year ago

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