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The mean number of days construction workers miss per year is 11. The standard deviation is 2.3. The mean number of days factory workers miss per year is 8 with a standard deviation of 1.8. Which class is more variable in terms of days missed?

Please show work.

User Manidhar Mulaparthi
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1 Answer

15 votes
15 votes

Answer:

Factory Workers

Step-by-step explanation:

While a common mistake may be to take in count of only the standard deviation (like I had done previously), there is an equation to use that measures the dispersion of data points in a data set around the mean, called coefficient of variation.


CV=(\sigma)/(\mu) *100 where sigma is the population standard deviation and mu is the population's mean.

The highest percentage of CV is considered more variable.

Let's do the math:

Construction workers:
(\sigma)/(\mu) =(2.3)/(11) =0.209*100=20.9%\\

Factory workers:
(\sigma)/(\mu) =(1.8)/(8) =0.225*100=22.5%

Since factory workers have a higher percentage, their data is more variable.

User Sky Fang
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