Seek the detailed explanation of the answer to the 22 nd question of Guangzhou mathematics senior high school entrance examination in 2008

Solution: If the speed of motorcycle is X km/h, the speed of emergency repair vehicle is1.5xkm/h.

30/x-30/ 1.5x= 15/60。

The solution is x=40.

Then1.5x =1.5x40 = 60 (km/h).

After investigation, x=40 is the solution of the original equation, which accords with the meaning of the question.

A: ...

Note: the exam is divided into two steps, one is the score equation, and the other is the application problem.