Final answer:
To find the average speed of the journey, add up all the distances and times, then divide the total distance by the total time. For this specific journey, the total distance is 1100 km and the total time is 22 hours, resulting in an average speed of 50 km/h.
Step-by-step explanation:
Calculating Average Speed
To calculate the average speed of a journey, you need to divide the total distance traveled by the total time taken. In the provided example, a car travels a distance of 300 km at a speed of 60 km/h, another 400 km in 9 hours, and the last part of the journey at 50 km/h for 8 hours. We need to sum up these distances and times to find the total distance and time.
First leg: 300 km / 60 km/h = 5 hours
Second leg: Time is already provided as 9 hours
Third leg: 50 km/h x 8 hours = 400 km, in 8 hours
Now, sum up the total distance and the total time:
Total distance = 300 km + 400 km + 400 km = 1100 km
Total time = 5 hours + 9 hours + 8 hours = 22 hours
The average speed then is:
Average speed = Total distance / Total time = 1100 km / 22 h = 50 km/h.