To calculate the deviation of a data point from the mean, you subtract the mean from the data point.
Given:
- Mean = 9
- Data point = 10
The deviation is calculated as follows:
\[ \text{Deviation} = \text{Data Point} - \text{Mean} = 10 - 9 = 1 \]
So, the deviation of the data point 10 from the mean 9 is 1.