25. Party A and Party B walk from A and B to each other at the speed of 4 kilometers and 5 kilometers per hour respectively. After meeting, they walked on. How many kilometers is there between A and B if A walks from the assembly point for another two hours and arrives at B?

Solution: The distance ratio when A and B meet = the speed ratio = 4: 5.

Then when they meet, A is 5/9 of the distance from the destination.

So AB distance = 4× 2/(5/9) = 72/5 = 14.4km.

26. Passenger cars and trucks depart from Party A and Party B relatively simultaneously. After meeting on the way, they moved on. They returned immediately after they arrived at each other's departure place. They met for the second time on the road. The distance between the two venues is120km. The bus travels 60 kilometers per hour and the truck travels 48 kilometers per hour. How many kilometers is the distance between Party A and Party B?

Solution: The speed ratio of passenger cars and trucks = 60: 48 = 5: 4.

Think of the whole distance as 1.

Then the first intersection is 1×5/(5+4)=5/9 from A.

The second encounter is three complete journeys.

Then the second intersection from B is1× 3× 5/9-1= 5/3-1= 2/3.

That is, the distance from A is 1-2/3= 1/3.

So the distance between Party A and Party B =120/(5/9-1/3) =120/(2/9) = 540 km.

for reference only