



 
Let's look at a similar example: The number of times an employee was observed to be working during the day was 36 out of a total of 50 random observations. Find the standard deviation. We can use the formula where σ is standard deviation, p is the proportion and n is the sample size. In this case p=36/50=0.72 and n=50 σ = √(0.72)(10.72)(50) = √(0.72)(0.28)(50) = √10.08 = 3.2 I hope this helps, Janice  


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