Two planes leave Chiago's O'Hare Airport at the same time, one traveling east and the other west. The average speed of the eastbound plane is 60 km/h...

Two planes leave Chiago's O'Hare Airport at the same time, one traveling east and the other west. The average speed of the eastbound plane is 60 km/h more than the speed of the westbound plane. After 2.5 h of flying time, the planes are 4150 km apart. What are their speeds?