The average speed is 12 km/hr.
It is to find the average speed in km /h.
What is speed?
Speed is measured as the ratio of distance to the time in which the distance was covered.
Given that :
Distance covered by Niamh = 6 km
Time =30minutes=30/60hour
=1/2hour
∴ The average speed=Total distance/Total time
The average speed=6*2/1
The average speed=12 km/hr.
So, the average speed is 12 km/hr.
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