Question

Гонцу надо было пробежать 24мили.Две трети этого он бежал со средней скоростью 8 миль в час. сможет ли он увеличил скорость пробежать остаток пути так чтобы его средняя скорость на всем пути оказалась равной 12 миль в час

Answer 1

Что такое средняя скорость
это весь путь на все время
, получается чтобы средняя скорость была 12 км/ч надо чтобы он бежал 2 часал, но тк он уже пробежал 2 часа и осталось 8 км, то как бы он не увеличивал скорость, но он не сможет пробежать весь путь со скоростью 12 км/ч

Answer 2

Problem Analysis

The problem states that a runner needs to run a total of 24 miles. Two-thirds of this distance is already covered at an average speed of 8 miles per hour. The question is whether the runner can increase their speed for the remaining distance so that their overall average speed becomes 12 miles per hour.

Solution

To solve this problem, we need to find the speed at which the runner needs to run the remaining distance to achieve an average speed of 12 miles per hour for the entire distance.

Let's calculate the distance the runner has already covered: - Two-thirds of 24 miles is (2/3) * 24 = 16 miles.

Now, let's calculate the time it took the runner to cover the first 16 miles: - Time = Distance / Speed = 16 miles / 8 miles per hour = 2 hours.

To find the remaining distance, we subtract the distance already covered from the total distance: - Remaining distance = Total distance - Distance already covered = 24 miles - 16 miles = 8 miles.

Now, let's calculate the time it would take the runner to cover the remaining 8 miles at an average speed of 12 miles per hour: - Time = Distance / Speed = 8 miles / 12 miles per hour = 2/3 hour.

To find the total time taken for the entire distance, we add the time taken for the first 16 miles and the time taken for the remaining 8 miles: - Total time = Time for first 16 miles + Time for remaining 8 miles = 2 hours + 2/3 hour.

Therefore, the runner can increase their speed to cover the remaining distance in such a way that their overall average speed becomes 12 miles per hour.

Conclusion

The runner can increase their speed to cover the remaining 8 miles so that their overall average speed for the entire 24-mile distance becomes 12 miles per hour. The total time taken would be 2 hours and 2/3 hour.

Please let me know if you need any further clarification.