A random sample of 35 trading days is taken and the volume of a particular stock is recorded to determine whether the mean volume of the stock has changed from its 2007 value of 35.14 million shares. The sample resulted in a mean trading volume of = 39.48. Assuming a population standard deviation of 15.07, compute the margin of error for a 95% confidence interval for m. I got 4.19 Is this correct?(adsbygoogle = window.adsbygoogle || []).push({});

Also, A random sample of 35 trading days is taken and the volume of a particular stock is recorded to determine whether the mean volume of the stock has changed from its 2007 value of 35.14 million shares. The sample resulted in a mean trading volume of = 39.48. Assuming a population standard deviation of 15.07, calculate a 95% confidence interval for m using a Z interval. I got (38.64, 40.32)

Is that correct or can it not be computed?

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# Homework Help: Confidence Intervals; Am I correct on these 2 problems?

Can you offer guidance or do you also need help?

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