Question

A train leaves San Diego at 1:00 pm. A second train leaves the same city in the same direction at 3:00 pm. The second train travels 30 mph faster then the first. If the second train overtakes the first at 6:00 pm, what is the the speed of each of the two trains?

Answer 1

Answer:

The speed of the first train is 45 mph and the speed of the second train is 75 mph

Step-by-step explanation:

Let x represent the speed of the first train in mph. Since the second train, is 30 mph faster then the first, therefore the speed of the second train is (x + 30).

The first train leaves at 1:00 pm, therefore at 6:00 pm, the time taken is 5 hours. Therefore the distance covered by the first train at 6:00 pm = x mph * 5 hours = 5x miles

The second train leaves at 3:00 pm, therefore at 6:00 pm, the time taken is 3 hours. Therefore the distance covered by the second train at 6:00 pm = (x + 30) mph * 3 hours = (3x + 90) miles

Since the second train overtakes the first at 6:00 pm, hence:

3x + 90 = 5x

2x = 90

x = 45

Therefore the speed of the first train is 45 mph and the speed of the second train is 75 mph (45 mph + 30 mph).