Let t be time in hours.
Train A travels at 100 km per hour, so after t hours it will be 100t km from the station.
Train B travels at 160 km per hour, but it leaves the station one and a half hours later than train A, so its time is (t-1.5) hours. After (t-1.5) hours it will be 160(t-1.5) km from the station.
Train B will overtake train A when their distances from the station are equal.
Train B will overtake train A after 4 hours since train A left the station. It left the station at 8:00, so train B will overtake it at 12:00.
Train A travels at 100 km per hour, so after t hours it will be 100t km from the station.
Train B travels at 160 km per hour, but it leaves the station one and a half hours later than train A, so its time is (t-1.5) hours. After (t-1.5) hours it will be 160(t-1.5) km from the station.
Train B will overtake train A when their distances from the station are equal.
Train B will overtake train A after 4 hours since train A left the station. It left the station at 8:00, so train B will overtake it at 12:00.