Xiaorong and Xiaoying have an appointment to meet at 2: 00 to 3: 00 pm. Because both of them are very busy, they can leave in 20 minutes. What are the chances of meeting?

5/9 Establish a rectangular coordinate system, with X as the abscissa and Y as the ordinate, indicating that the time unit of B is minutes, and the sum * * * is 60*60. Because the absolute value of x-y is less than or equal to 20, the qualified formula is | X-Y |.