Respuesta :
The mean of the stock's returns over the past 3 years minus the sample standard deviation of the stock's returns from the past 3 years is -6.54
What is the standard deviation?
A standard deviation is a measurement of the data's dispersion from the mean. Data are grouped around the mean when the standard deviation is low, and are more dispersed when the standard deviation is high.
Standard deviation It is a measure of how spread out numbers are. It is the square root of the Variance, and the Variance is the average of the squared differences from the Mean.
Mean :
Mean = [10+3 + (-7) ] / 3 = 2
sample standard deviation :
subtract the mean from each data element.
10- 2 = 8
3-2 = 1
-7 - 2 = -9
Square those numbers.
8² = 64
1² = 1
(-9)² = 81
Add those
64+1+81 = 146
Divide by (number of elements -1 = 3 -1 = 2)
146/2 = 73
Take square root
8.54
So, the sample standard deviation = 8.54
The mean of the stock's returns over the past 3 years minus the sample standard deviation of the stock's returns from the past 3 years
= 2 - 8.54
= -6.54
To learn more about the standard deviation from the given link
https://brainly.com/question/12402189
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