Question 21
A thief takes an athlete’s bag and runs at 9 km/h. Fifteen minutes later, the athlete starts chasing at 15 km/h with his dog, which runs at 24 km/h. The dog runs to the thief, back to the athlete, and repeats until the athlete catches the thief. All follow the same route at constant running speeds, with immediate turns. How far does the dog run, in kilometres?
