(280-240)x=400
40x=400
x= 10
A: 10 minutes later, A ran one lap more than B.
Suppose two cars meet after x hours.
(95+85)x=270
180x=270
x= 1.5
95× 1.5 = 142.5km
A: After 1.5 hours, the two cars will meet, and the meeting place is 0/42.5 kilometers away from Shanghai/kloc-0.
(When the unit is kilometers, answer question 2,270)
(1) How about the teacher's qualification certificate for the high school math exam?
High school students are definite