Mean = 100
Standard Deviation = 25
(120 -100) / 25 = 0.80
th z value of .80 from the table = .2881
P(100-120) = 28.81%
What percentage of calls are completed in less than 60 minutes ?
(60 - 100) / 25 = - 1.6
from the table the z value is .4452
(one side), then : .5000 - .4452 = .0548
P(60) = 5.48%
34.1% with the normal distribution.
Standard deviation is the variance from the mean of the data.
The mean is the average value and the standard deviation is the variation from the mean value.
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Standard deviation is a calculation. It I used in statistical analysis of a group of data to determine the deviation (the difference) between one datum point and the average of the group.For instance, on Stanford-Binet IQ tests, the average (or, mean) score is 100, and the standard deviation is 15. 65% of people will be within a standard deviation of the mean and score between 85 and 115 (100-15 and 100+15), while 95% of people will be within 2 standard deviations (30 points) of the mean -- between 70 and 130.
Standard deviation doesn't have to be between 0 and 1.
Standard deviation is the square root of the variance.
34.1% with the normal distribution.
Standard deviation is the variance from the mean of the data.
Standard error of the mean (SEM) and standard deviation of the mean is the same thing. However, standard deviation is not the same as the SEM. To obtain SEM from the standard deviation, divide the standard deviation by the square root of the sample size.
The distance between the middle and the inflection point is the standard deviation.
The mean is the average value and the standard deviation is the variation from the mean value.
The standard deviation is the square root of the variance.
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The area between the mean and 1 standard deviation above or below the mean is about 0.3413 or 34.13%
The more precise a result, the smaller will be the standard deviation of the data the result is based upon.
Standard error is the difference between a researcher's actual findings and their expected findings. Standard error measures the accuracy of one's predictions. Standard deviation is the difference between the results of one's experiment as compared with other results within that experiment. Standard deviation is used to measure the consistency of one's experiment.