Mr Brown lives in Middleton, and his house is an easy walk from Middleton railway station.
There is a railway line running through Middleton station going from Easton station to Weston station, and Middleton station is exactly halfway between Easton station and the Weston station, on this railway track.
Trains run from Easton station via Middleton station to Weston station every ten minutes. Also, Trains run from Weston station via Middleton station to Easton station every ten minutes.
Every morning Mr Brown gets up, has his breakfast, does his chores for the day and then starts walking to Middleton station. He is not a creature of habit, and sets out on his walk to Middleton station at different times each day, depending on the time he wakes up and the length of time he spends on breakfast and his chores. For the purpose of this puzzle he starts on his walk at a random time each day.
Mr Brown has no preference as to whether he goes to Easton or Weston, and so he catches the first train to arrive at Middleton station and goes to whichever town the train going to.
Oddly, he goes to Easton nine times as often as he goes to Weston!
Imagine that the trains to Easton arrive in Middleton on the hour, and then at 10 minutes past, 20 minutes past, half past, 20 minutes to and 10 minutes to the hour.
The trains to Weston arrive at 1 minute past the hour, and then at 11 minutes past, 21 minutes past, 29 minutes to, 19 minutes to and 9 minutes to the hour.
Thus in each period of ten minutes Mr Brown has a one-minute window where the next train is to Weston, and a nine-minute window where the next train is to Easton. If he arrives at a random time each day, he is nine times more likely to catch a train to Easton.