The tram passed the first 100 meters at a speed of 18 km / h, and the next 200 meters at a speed

The tram passed the first 100 meters at a speed of 18 km / h, and the next 200 meters at a speed of 36 km / h. What is the average speed of the tram along the entire route.

Let’s define the entire tram route. It is equal to 100 m + 200 m = 300 m. Let’s find all the time spent on all sections of the path. It is equal to (100 m) / (18 km / h) + (200 m) / (36 km / h) = (100/18000 + 200/36000) h = (5/900 + 5/900) h = 1 / 90 hours. To find the average speed, the length of the entire path is divided by the entire time of movement. Therefore, it is equal to (300 m): (1/90 h) = (300: 1000 km): (1/90 h) = (0.3 * 90) km / h = 27 km / h.