Hehe, your topic may be:
The distance between Station A and bilibili is 365 kilometers. A local train runs from Station A to bilibili at a speed of 65 kilometers per hour. After the local train runs 1h, the express train goes from bilibili to Station A with an hourly journey of 85km. How long does it take for the express train to meet the local train?
If this is the topic, you can do this:
(365-65* 1)/(65+85)
=300/ 150
=2 (hours)