Speed Time And Distance

Step 1: Understanding the Concept:
Average speed is not the average of the speeds. It is calculated by dividing the total distance traveled by the total time taken for the journey.

Step 2: Key Formula or Approach:
1. Calculate the total distance traveled.
2. Calculate the time taken for each segment of the journey using the formula: Time = Distance / Speed.
3. Calculate the total time taken.
4. Calculate the average speed using the formula: Average Speed = Total Distance / Total Time.

Step 3: Detailed Explanation:
1. Total Distance:
The total distance is the sum of the distances of the three segments: 2. Time for each segment:


Time for the first segment ( ): Distance = 5 km, Speed = 10 km/hr.
Time for the second segment ( ): Distance = 3 km, Speed = 8 km/hr.
Time for the third segment ( ): Distance = 2 km, Speed = 5 km/hr. \end{itemize} 3. Total Time:
The total time is the sum of the times for each segment: 4. Average Speed:
Now, we calculate the average speed:
Step 4: Final Answer:
The average speed of the cyclist during the whole journey is approximately 7.84 km/hr.