DAY 54

Comment

There is not much evidence to go on.
For all we know, there might be just 1 bus an hour (in which case Sue was lucky only to have to wait 6 minutes);
or there might be 1 bus every 10 minutes (in which case Sue was a bit unlucky to have to wait 6 minutes).
What is the best estimate we can make on the available evidence?

Answer

5 buses per hour.

Readers' methods

Reg Farndel, Dublin:
My best guess is a bus every 12 minutes, because then you would expect to wait 6 minutes on average for a bus.
A bus every 12 minutes is 5 buses every hour.

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