97.ab is 60 kilometers apart. A rides a bike from a to b. After 2 hours and 30 minutes, B rode a motorcycle from A to B. As a result, B arrived at B earlier than A 10 minutes. It is known that the speed of B is five times that of A. What is the speed of B?

Solution: 2 hours and 30 minutes = 150 minutes.

If Party A and Party B leave at the same time, Party B will arrive at B earlier than Party A150+10 =160.

So at the same distance, the time ratio of Party A and Party B = the inverse ratio of speed = 5: 1.

Then the time taken for the whole journey of line B is 0/5 of that of line A+65438.

Therefore, the whole journey time of Line A =160/(1-1/5) = 200 minutes.

Time taken for the whole journey of the second line =200- 160=40 minutes =2/3 hours.

Speed b = 60/(2/3) = 90km/h.

98. The distance between Party A and Party B is 960 kilometers. The express train leaves Station A for bilibili at 5 a.m., and the local train leaves bilibili for Station A at the same time. The two trains meet at 1 1 in the morning. When will the express train arrive at bilibili at 3 pm and the local train arrive at Station A?

Solution: 165438+ 0 am to 3 pm * * * is 4 hours.

Meeting time = 1 1-5=6 hours.

Time for the express train to complete the journey =6+4= 10 hour.

Express speed = 960/10 = 96 km/h.

The sum of the speeds of two vehicles = 960/6 =160 km/h.

The speed of the local train =160-96 = 64 km/h.

It takes 960/64= 15 hours for the local train to complete the journey.

So the time for the local train to arrive at Station A is 5+ 15=20 in the afternoon.