Recent content by hollyinscotland

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    Confusing question on z-score for sample mean

    Thanks for your answer, but I am not sure how this adds up to the calculation of the website. The website says: S.D.=4.29/30−−√=.78 Z=(8.4−7)/.78=1.8 From the Z-table: 1.8 corresponds to .9641; p= 1 - .9641 = .036 We reject the null hypothesis since 1.8 > 1.64 (and .036 is less than 95%)...
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    Confusing question on z-score for sample mean

    Hey folks, I was hoping someone would understand this better than I do. I am trying to solve the following problem: We are testing the hypothesis that the average gas consumption per day in Billings, Montana is greater than 7 gallons per day; we want 95% confidence. We sample 30 drivers. The...