Speed, Distance and Time
The following is a basic but important formula which applies when speed is constant (in other words the speed doesn't change):
Remember, when using any formula, the units must all be consistent. For example speed could be measured in m/s, distance in metres and time in seconds.
If speed does change, the average (mean) speed can be calculated:
Average speed = total distance travelled
total time taken
In calculations, units must be consistent, so if the units in the question…