Final answer:
The train took 6 hours to complete a journey of 240 miles at a speed of 40 mph by using the formula Time = Distance / Speed and solving for Time.
Step-by-step explanation:
To calculate the time it took for the train to complete its journey, we use the formula for speed, which is distance divided by time (Speed = Distance / Time). We are given that the train travels at a speed of 40 mph (S = 40 mph) and covers a distance of 240 miles (D = 240 miles). We're looking for the time (T).
The formula can be re-arranged to solve for time: Time = Distance / Speed. Plugging in our values we get Time = 240 miles / 40 mph. This calculation gives us the time it took for the train to travel 240 miles.
Time = 240 miles / 40 mph = 6 hours. So, it took the train 6 hours to complete its journey.