Solution: if the distance between the two places is s meters and it takes t to meet for the first time, then:

The speed of A is 40/t, and the speed of B is (S-40)/t. ..

From the first meeting to the second meeting, the two spent almost the same time.

A time: (40+90)/ (40/t)

B time: [(S-40)+(S-90)]/(S-40)/t,

So: (40+90)/(40/t) = [(S-40)+(S-90)]/(S-40)/t.

Solution: S= 105 (km)