At the same time, the distance is proportional to the speed. The speed ratio of Party A and Party B is 2: 3, and the distance ratio of Party A and Party B is 2: 3. Because two people meet for the first time at point C 80 meters away, and Party A walks very slowly. So the distance of A is 80 meters. So the distance of b is 120 meters. So the circumference is 200 meters. I hope it helps you!