Two travelers set out at the same time to travel opposite ways round a circular railway. Trains start each way every fifteen minutes: on the hour, fifteen minutes past, half past, and forty-five minutes past. Clockwise trains take two hours for the journey, counterclockwise trains take three hours.
Including trains seen at the starting point and the ones they are traveling on, how many trains did each traveler see on his journey?
(In reply to
solution by Charlie)
Ch,<o:p></o:p>
Both you and I placed erroneous answers .<o:p></o:p>
I have
typed wrong arrival hours and YOU HAVE MISSED ONE TRAIN- EITHER THE ONE THAT
arirves as you leave or the one that leaves exactly as you arrive).<o:p></o:p>
Here is
the right one (same reasoning , but correct TOA):<o:p></o:p>
CORRECT
ANSWERS:<o:p></o:p>
1st
trav & 2nd trav -22 trains.++<o:p></o:p>
Assume
that the clockwise train left at 12:00 and finished its round at 14:00 - he met
the trains that left between 9:00 and 14:00 inclusive
i.e. 5*4*1=21, SINCE THERE ARE 20 INTERVALS REPRESENTING 21 TRAINS
. ADD YOUR OWN TRAIN - THAT means 22 trains were seen.<o:p></o:p>
Apply the
same reasoning to the other train: left at 12:00 and finished its round at
15:00 - he met the trains that left between 10:00 and 15:00 inclusive
i.e. 21 that means 22 trains were seen. <o:p></o:p>
re: solution
