To estimate the mean size of maple trees in a certain area of the Adirondacks, a...

To estimate the mean size of maple trees in a certain area of the Adirondacks, a simple random sample of 20 maple tree heights is collected (assume the population of tree heights is normally distributed). Please refer to the data set for your tree heights.

24	47	52	58	41	37	56	63	39	32
24	29	52	33	47	40	56	52	54	31

a) Using the formula for confidence intervals, create a 95% confidence interval for the population mean of maple tree heights.

b) Using the formula for confidence intervals, create a 98% confidence interval for the population mean of maple tree heights.

c) What size sample would you need to estimate the population average heights of the maple trees with an error of 0.1 feet at a 90% level of confidence? Assume population standard deviation is 10.2 feet.

Expert Solution

Xi	(Xi-Xbar)²
24	374.4225
47	13.3225
52	74.8225
58	214.6225
41	5.5225
37	40.3225
56	160.0225
63	386.1225
39	18.9225
32	128.8225
24	374.4225
29	205.9225
52	74.8225
33	107.1225
47	13.3225
40	11.2225
56	160.0225
52	74.8225
54	113.4225
31	152.5225
867	2704.55

orchestra answered 2 years ago

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