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17 votes
17 votes
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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