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In a certain county in New York state, the mean monthly utility bill per household is $295 with a standard deviation of $30. The monthly bill per household is normally distributed. If a random sample of 25 households is selected from this county, what is the probability that the sample mean monthly utility bill will be more than $290? Give your answer to four decimal places. [a]

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Using

Given
\begin{gathered} x=290 \\ \mu=295 \\ \sigma=30 \end{gathered}Solution
\begin{gathered} Z=(290-295)/(30) \\ \\ Probabilityofx>290:0.56618 \end{gathered}The final answer

In a certain county in New York state, the mean monthly utility bill per household-example-1
User Billinkc
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