Let the distance be z, t 1 be the first meeting, and t2 be the second meeting.

t 1/t2=90/(z+60)

t 1/t2=(z-90)/(2z-60)

z？ -2 10z=0

z=2 10

2 10/0km apart.

90×3-60=2 10

The distance from A90 for the first time is 90 meters, that is, the distance from A to the second meeting is three times, so A ×3, at this time, is 60 meters away from B, that is, A walks 60 meters more than the whole journey, so subtract 60 to get the distance between A and B.