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Calculating Confidence Interval for Population Means

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A researcher desires to estimate the difference in means of two populations. To accomplish this, she takes a random sample of 81 items from the first population. The sample yields a mean of 168 with a variance of 324. A random sample of 64 items is taken from the second population yielding a mean of 161 with a variance of 625. Compute a 94% confidence interval for the difference in population means.

My calculation comes up with 1.25 to 10.49. Is this correct?

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Calculating Confidence Interval for Population Means is provided.

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