Answer:
The standard deviation of the sample mean is 16.98.
Explanation:
The standard deviation of the sample mean differences is given as by the difference of the 2 standard deviations.This is given as
Difference of standard deviations=21.2-17.6 = 3.6
Now the ratio of the difference to the largest standard difference is given as
Ratio=3.6/21.2=0.1698
Converting this into percentage as 0.1698x100=16.98
The standard deviation of the sample mean is 16.98.
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Answer: The factory system was a new way of making products that started during the Industrial Revolution.