To find the average speed of the car, we can use the formula:
Average Speed = Total Distance / Total Time
Let's assume the total distance is "D" kilometers.
The car travels the first half of the distance, which is D/2 kilometers, at a speed of 30 km/h. The time taken to cover this distance can be calculated as follows:
Time taken for first half = Distance / Speed = (D/2) / 30 = D / (2 * 30) = D / 60 hours
Next, the car travels the remaining half of the distance, which is also D/2 kilometers, at a speed of 50 km/h. The time taken to cover this distance can be calculated as follows:
Time taken for second half = Distance / Speed = (D/2) / 50 = D / (2 * 50) = D / 100 hours
The total time taken to cover the whole distance is the sum of the time taken for the first half and the time taken for the second half:
Total Time = Time for first half + Time for second half = D / 60 + D / 100
To get the average speed, we divide the total distance by the total time:
Average Speed = Total Distance / Total Time = D / (D / 60 + D / 100)
Now, let's simplify this expression:
Average Speed = D / [(D * 100 + D * 60) / (60 * 100)] Average Speed = D / [(D * 160) / (60 * 100)] Average Speed = D / (16D / 6) Average Speed = 6 / 16
Average Speed = 0.375
So, the average speed of the car over the entire distance is 0.375 km/h, which is equivalent to 375 meters per hour.