A freight train and a passenger train leave a rail yard at the same time and travel on parallel tracks. The passenger train travels 6 mph faster than the freight train. The combined distance traveled after 2 hours is 100 miles. What's the average speed of each train?

The freight train speed = 22 mph

The passenger train speed = 28 mph

Step-by-step explanation:

Assign the speed of the freight train as; x mph

Since the passenger train travels 6 mph faster than the freight train, its speed will be; (x + 6) mph

In 2 hours, the freight and passenger trains will have traveled (distance = speed * time);

2x and 2 (x + 6) miles respectively

Both add up to 100 miles. Therefore;

2x + 2 (x + 6) = 100

4x + 12 = 100

4x = 88

x = 22

x + 6 = 28

The freight train speed = 22 mph

The passenger train speed = 28 mph