Analysis: The application problems of senior one are all the same steps: examining the problems, setting unknowns, finding equivalence relations, listing equations, solving equations, verifying and answering.

I will follow this step to demonstrate this problem:

Car B left 1.5 hours, and car A left earlier than car B 15 minutes, so car A left for 0.25 hours, that is, car A left 1.75 hours, and the time was up.

The speed of car B is 1.5 times that of car A. If car A is X, then car B is 1.5x, and the speed is also acceptable.

When they met, car A walked 6 kilometers less than car B, which tells us the equal relationship, that is, the distance between car B and car A =6, and the distance = speed multiplied by time.

Solution: Let the speed of A be x km/h, then the speed of B is 1, 5xkm/h.

1.5 * 1.5x- 1.75 x = 6

2.25x- 1.75x=6

0.5x=6

x= 12

Speed of B: 1.5* 12= 18 (km/h)

A: Omit ~