The train covered 60 km in 1 hour, then it moved for another 30 minutes at a speed of 90

The train covered 60 km in 1 hour, then it moved for another 30 minutes at a speed of 90 km per hour. Determine the average train speed

Average train speed:

Vav. = S / t, where S is the total distance traveled by the train (S = S1 + S2, where S1 = 60 km), t is the total travel time of the train (t = t1 + t2, where t1 = 1 h, t2 = 30 min = 0.5 h).

Track section S2:

S2 = V2 * t2, where V2 = 90 km / h.

Let’s calculate the average speed of the train

Vav. = (S1 + S2) / (t1 + t2) = (S1 + V2 * t2) / (t1 + t2) = (60 + 90 / 0.5) / (1 + 0.5) = (60 + 45) / 1.5 = 105 / 1.5 = 70 km / h.

Answer: The average train speed is 70 km / h.