A city has a bicycle hire scheme where it is possible to hire a bicycle for short journeys.  Last year I hired a bicycle $$60$$ times and rode for $$13$$ hours altogether.  For how long on average did I hire the bicycle on each ride? 
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The rider travels for $$13$$ hours over $$60$$ rides, which is anaverage time of $$\frac{13}{60}$$ of an hour per ride, hence $$13$$ minutes. 