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Chapter 4: Q131E (page 271)

4.131 Chemical composition of gold artifacts. The Journal of Open Archaeology Data(Vol. 1, 2012) provided data onthe chemical composition of more than 200 pre-Columbiangold and gold-alloy artifacts recovered in the archaeologicalregion inhabited by the Muisca of Colombia (a.d.600鈥�1800). One of many variables measured was the percentageof copper present in the gold artifacts. Summary statisticsfor this variable follow: mean = 29.94%, median = 19.75%,standard deviation = 28.37%. Demonstrate why the probabilitydistribution for the percentage of copper in thesegold artifacts cannot be normally distributed.

Short Answer

Expert verified

So here mean and median are not the same, hence the probability distribution cannot have a normal distribution.

Step by step solution

01

Given information

One of many variables measured was the percentageof copper present in the gold artifacts. Summary statisticsfor this variable follow: mean = 29.94%, median = 19.75%,standard deviation = 28.37%.

02

Explanation

The property of normal distribution is mean=median

Here the mean is 29.94% and the median is 28.37%.

So here mean and median are not the same, and therefore the probability distribution cannot have a normal distribution.

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