Question

Одну третину шляху автомобіль рухався зі швидкістю 80км/год ,а останній шлях -зі швидкістю 40км/год. Визначити середню швидкість автомобіля

Answer 1

50км/год....................

Answer 2

Calculation of Average Speed

To calculate the average speed of the car, we need to consider the distance traveled at each speed and the time taken for each segment.

Let's assume that the total distance traveled by the car is D.

According to the given information, the car traveled two-thirds (or one-third less) of the distance at a speed of 80 km/h and the remaining one-third of the distance at a speed of 40 km/h.

The distance traveled at a speed of 80 km/h is (2/3)D, and the distance traveled at a speed of 40 km/h is (1/3)D.

The time taken to travel the distance at a speed of 80 km/h can be calculated using the formula:

Time = Distance / Speed

Therefore, the time taken to travel (2/3)D at a speed of 80 km/h is (2/3)D / 80.

Similarly, the time taken to travel (1/3)D at a speed of 40 km/h is (1/3)D / 40.

To calculate the average speed, we can use the formula:

Average Speed = Total Distance / Total Time

The total distance is D, and the total time is the sum of the times taken at each speed:

Total Time = (2/3)D / 80 + (1/3)D / 40

Now, let's substitute the values and calculate the average speed.