Let's meet together #5 - a Physics problem

The distance between A and B is 300 km. At 6 am, a motorbike travels from A to B with a constant velocity of $50 km/h$ . At 7 am, a car travels from B to A with a constant velocity of $75 km/h$ . On the road, there is a bike which is always in the middle of the motorbike and the car (in other words, the bike always keeps the same distance from the car and the motorbike). The bike starts at the same time as the car. (Assume the bike travels with a constant velocity)

What is the bike's constant velocity? Type your answer in $km/h$ and to only 1 decimal.

Note: All motions mentioned in the problem are linear motions

Part 1

Part 2

Part 3

Part 4