Question: A certain commodity is known to have a price that
A certain commodity is known to have a price that is stable through time and does not change according to any known trend. Price, however, does change from day to day in a random fashion. If the price is at a certain level one day, it is as likely to be at any level the next day within some probability bounds approximately given by a normal distribution. The mean daily price is believed to be $14.25. To test the hypothesis that the average price is $14.25 versus the alternative hypothesis that it is not $14.25, a random sample of 16 daily prices is collected. The results are x-bar = $16.50 and s = $5.8. Using α = 0.05, can you reject the null hypothesis?
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