Question

A cattle train left Miami and traveled towards New York. 14 hours later a diesel train left traveling at 45 km/h in an effort to catch up to the cattle train. After traveling for four hours the diesel train finally caught up. What was the cattle train's average speed?

The cattle train's average speed was
km/h.

Answer 1

10 km/h

Explanation:

You want the speed of one of two trains that meet after the first one has a 14-hour head start. The time and speed of the second train are given.

Distance to the meeting point

The relation between time, speed, and distance is ...

distance = speed × time

distance = (45 km/h)(4 h) = 180 km

The diesel train catches the cattle train after they both have traveled 180 km.

Speed of cattle train

The cattle train travels 14 hours before the diesel train starts plus the 4 hours after the diesel train starts by the time the two trains meet. In that 18 hours, it has also traveled 180 km. Its average speed is ...

speed = distance / time

speed = (180 km)/(18 h) = 10 km/h

The speed of the cattle train is 10 km/h.