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Sampling Error Analysis - M&Ms

I have an assignment in which I am to calculate the sampling error from a bag of M & M's.
the directions were to go buy a bag of M & M's from the store and count the colors. The go to M & M's web site and get the % counts of each color.

Compare your counts (%) to those of the M & M web site.

Calculate your sampling error as a plus (+/-) or minus percentage for each color.

I calculated it this way but am wondering if I should have used the formula in the lower half. I would like to see an example of this formula using my figures so I can see how to plug the numbers in. I want to be compete in this assignment before i go to teacher to see which formula is correct one.

Total pieces was 57

Color Website Count (%) M&M Count (%) Sampling Error +/-
Blue 23.2% 24% -.8%
Red 10.7% 13% -2.3%
Yellow 12.5% 14% -1.5%
Orange 17.9% 20% -2.1%
Green 17.9% 16% 1.9%
Brown 17.9% 13% 4.9%

Sampling Error is calculated by using the formula

Sampling Error = Statistic - Parameter

In this case Statistic is sample proportion for each color and Parameter is proportion for each color from website.

Or

should it be calculated this way ( please use this formula and calculate sampling error for the different colors of M & M's.

The relationship between sampling error, a percentage measure and a
sample size can be expressed as a formula.

e = z (square root of) p%(100-p%))
----------------------------------------------
square root (s)

Where:

e = sampling error (the proportion of error we are prepared to accept)

s = the sample size

z = the number relating to the degree of confidence you wish to have in the result

p = an estimate of the proportion of people falling into the group in which you are interested in the population

Solution Summary

Sampling error analysis for M&Ms is discussed. The solution compares your count percents to those of the M&M website.

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