Calculate the standard deviation from the formula
The table shows the distance, in kilometres, travelled to work by four employees at a company, with the working for the standard deviation partly filled in
| Distance (km) | Deviation | Squared deviation |
|---|---|---|
| 25 | 6 | 36 |
| 17 | -2 | 4 |
| 17 | -2 | 4 |
| 17 | -2 | 4 |