Final answer:
A decrease in the speed of a train would lead to covering a shorter distance in the same amount of time, as average speed is directly related to the distance traveled when time is constant.
Step-by-step explanation:
The question pertains to the concept of average speed and how it affects the distance traveled by a train over a period of time. Average speed is defined as the total distance traveled divided by the total time taken to travel that distance. Using the examples provided for reference, we can determine how a decrease in speed will impact the distance covered by the train within a given time frame.
For instance, if a car travels 150 kilometers in 3.2 hours, the calculation of its average speed would be:
Vavg = distance / time = 150 km / 3.2 h = 47 km/h.
Similarly, we calculate the average speed of a train that travels 40 miles out and 40 miles back. The total distance is 80 miles. If the train's speed were to decrease, the distance covered in the same amount of time would consequently be less. This is because speed and distance are directly proportional when time is held constant.