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# Confidence Interval for Mean Difference

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1. 12 mature citrus trees of one variety and 15 of another gave means and standard deviations of their heights as 13.8 and 12.9 ft (means), and 1.2 and 1.5 ft (standard deviations).
Find a 95% confidence interval for the true difference in average heights between all trees of the first and the second variety.
Would you be able to validate the assumptions in this case?

2. 25 observations are collected from a normal distribution with variance 4. give a number 'c' such that the sample mean is within a distance 'c' from the population mean with a probability of 95%.

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Confidence Interval
1. 12 mature citrus trees of one variety and 15 of another gave means and standard deviations of their heights as 13.8 and 12.9 ft (means), and 1.2 and 1.5 ft (standard deviations).