100 days should it sample so that the margin of error will be 39.1 tons or less
What is margin error?
The margin of error is a statistic that describes how much random sampling error there is in survey results. One should have less faith that a poll's findings would accurately reflect those of a population census the higher the margin of error.
The margin of error can be stated as
ME = SE⋅cv where cv = z.90 because this corresponds to a two tail test so we need the z value at 90%.
We can now use a look up table to find the corresponding z value to use which should be 1.96
Now
SE = σ/√n leading to
39.1 = (197/√n)⋅(1.96).
Now we just need to solve for n
√n = (197/39.1)⋅(1.96) = 10
n = 10^2
n = 100
So, we probably need to sample for about 100 days if we want be within that margin of error.
To know more about the margin error, click on the link
https://brainly.com/question/24289590
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