Beth caught the train from London to Leeds. It arrived in Leeds $$5$$ minutes late. This wasn\textquotesingle t too bad as it had left London $$15$$ minutes late. The journey took $$\frac{11}{12}$$ of the time it should have done. How long should the Journey have taken?  Answer:~\uline{~~~~~~~~~~}~ 
Overseas Competition->Knowledge Point->Combinatorics->Time Problem->Time Calculation