Three friends A, B and C regularly jog in a circular jogging track every morning. The track is 1000 m in circumference.

A takes 8 mins to complete one lap, B takes 10 mins and 40 secs and C takes 12 mins. All of them setout from a same point but C runs in the opposite direction from starting point.

Another friend D joins this run. D normally takes 13 mins and 20 secs to complete one lap. He decides to run in the same direction as C but from a point 600 m ahead of C in his jogging direction. When will they all meet each other on the circular track & where?

They'll all meet at 11520 seconds (192 minutes) at the starting line.

There are 3 way meetings of A, B and D at 1192 and of A, D and C at 4320 seconds etc. (and A, B and C at 5760 sec. see Part 1)

There is a near miss of all four around 4000 seconds near the 350 meter mark where A passes D then C a minute so so later  B passes them as well.

Posted by Jer on 2006-04-13 14:10:13