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A company is interested in lumbering rights for slash pine trees. The mean diameter is 16 inches with a standard deviation of 2.8 inches.

What fraction of the trees will have diameters between 10.4 and 24.4 inches?

a) Approximately 68%
b) Approximately 95%
c) Approximately 99.7%
d) The question does not provide sufficient information.

User Artur A
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1 Answer

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Final answer:

The question involves the normal distribution of slash pine tree diameters. The range given falls within two standard deviations of the mean, so approximately 95% of the trees will have diameters within that range.

Step-by-step explanation:

The question is asking what fraction of the slash pine trees will have diameters between 10.4 and 24.4 inches given that the mean diameter is 16 inches with a standard deviation of 2.8 inches. This is a statistics problem involving the properties of the normal distribution. For a normal distribution, approximately 68% of the data falls within one standard deviation of the mean, 95% within two standard deviations, and 99.7% within three standard deviations.

Given that the range from 10.4 to 24.4 inches spans from 2 standard deviations below the mean to 2 standard deviations above the mean (16 - 2(2.8) = 10.4 and 16 + 2(2.8) = 24.4), we can use the empirical rule to determine the fraction of trees in this range.

Therefore, the correct answer is (b) Approximately 95%, since the range of diameters spans 4 standard deviations, covering approximately 95% of the distribution around the mean.

User Kwexi
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