Roberto did not include the first term of the numerator (0-2)^2 in his calculation.
The mean of the data is also known as average.
Given the set of data 0, 2, 1, 2, 5
Mean = 0+2+1+2+5/5
Mean = 10/5
Mean = 2.0
To get the standard deviation, we will use the SD formula as shown:
[tex]\sigma=\sqrt{\frac{\sum (x-\overline x)^2}{N} }[/tex]
[tex]\sigma =\sqrt{ \frac{(0-2)^2+(2-2)^2+(1-2)^2+(2-2)^2+(5-2)^2}{5}}\\ \sigma = \sqrt{\frac{4+0+1+0+9}{5}} \\\sigma = \sqrt{\frac{14}{5} }\\\sigma = 1.673[/tex]
Comparing this with Roberto's calculation, we can see that Roberto did not include the first term of the numerator (0-2)^2 in his calculation.
Learn more here: https://brainly.com/question/10557301
