1, Party A and Party B respectively set out from A and B at the same time and walked towards each other at a constant speed. The place where they met for the first time is 4 kilometers away from A. After meeting, they continue to move forward and return immediately after reaching the starting point of the other party. The place where they met for the second time is 3 kilometers away from B. Find the distance between the two meeting places.

Solution: When they meet for the second time, they always walk three full distances, so A walked four kilometers, and the three should walk four kilometers.

Through drawing, we found that A walked the whole journey back, which is 3 kilometers away from B, so the whole journey is 12-3=9 kilometers.

So the distance between two intersections is 9-(3+4) = 2km.

2. Party A, Party B and Party C walk together. Party A walks 60 meters per minute, Party B walks 67.5 meters per minute and Party C walks 75 meters per minute. Party A and Party B go from Dongzhen to Xizhen, and Party C goes from Xizhen to Dongzhen. Three people start at the same time. After meeting Party B, they will meet Party A in two minutes. What is the distance between the two towns?

Solution: Those two minutes are the time when A and C meet, so the distance is (60+75)×2=270 meters, which is the distance difference between A and B when B and C meet.