SOLUTION: The average yearly cost per household of owning a dog is $186.80. Suppose that we randomly select 50 households that own a dog. What is the probability that the sample mean for t

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Question 215090This question is from textbook Elementary Statistics
: The average yearly cost per household of owning a dog is $186.80. Suppose that we randomly select 50 households that own a dog. What is the probability that the sample mean for these 50 households is less than $175.00? assume o=$32
* The book i am using gave me the formula value-mean/standard diveation. But me and my mother have been looking at this problem for at least 30 minutes and still just cant figure it out. plzz help me!! This question is from textbook Elementary Statistics

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
The average yearly cost per household of owning a dog is $186.80. Suppose that we randomly select 50 households that own a dog. What is the probability that the sample mean for these 50 households is less than $175.00? assume o=$32
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Find the z-value of 175.00:
z(174) = (175-186.80)/[32/sqrt(50)] = -11.80/[4.5255] = -2.6075
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P(x < 175) = P(z < -2.6075) = 0.00456
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Cheers,
Stan H.