1. Party A and Party B are on the 400-meter circular runway, and at the same time walk in the opposite direction from point. Party A walks 6 meters per second and Party B walks 4 meters per second. How long was the second time they met? 400 * 2/(6+4) = 80 seconds
The fundamental problem of many encounters on the roundabout is that their distance difference is the circumference of the roundabout when they meet. At this time, it depends on whether they face each other but walk in the same direction. The meeting time is equal to the length of the circular road divided by the speed difference, and the meeting time in the same direction is equal to the length of the circular road divided by the speed sum. I hope it helps you,