Statistics

The standard deviation (SD) is affected by a constant factor.
If each observation is divided by a constant, the SD is divided by the same constant.
So, if the original SD is 8 and each observation is divided by -2, the new SD will be:

We are given that the arithmetic mean is 7. The formula for the arithmetic mean is: However, without knowing the values for and , we cannot determine the sum of . Hence, it cannot be determined.

The standard deviation of data is not affected by an additive constant. Adding a constant value to each observation in the dataset will shift the data, but the spread (and thus the standard deviation) remains unchanged. Therefore, the new standard deviation is still 6.