Question

Расстояние между городами А и В равно 240 км. Из города А в город В выехал автомобиль со скоростью 60 км/ч, а через 30 мин навстречу ему из города В выехал мотоциклист со скоростью, меньшей скорости автомобиля на 20 км/ч. Через какое время после выезда мотоциклиста автомобиль и мотоцикл будут на расстоянии 20 км друг от друга?

Answer 1

Через 2.2 часов они встретятся!

Answer 2

Calculation of Time for the Car and Motorcycle to be 20 km Apart

To calculate the time it takes for the car and motorcycle to be 20 km apart, we need to consider their relative speeds and the time it takes for them to cover the initial distance of 240 km.

Given: - Distance between city A and city B: 240 km - Car speed: 60 km/h - Motorcycle speed: 60 km/h - 20 km/h = 40 km/h (since the motorcycle's speed is 20 km/h less than the car's speed)

To find the time it takes for the car and motorcycle to be 20 km apart, we can set up the following equation:

Time taken by the car to cover the distance + Time taken by the motorcycle to cover the distance = Total time

Let's calculate the individual times:

1. Time taken by the car to cover the distance: - Distance = 240 km - Speed = 60 km/h - Time = Distance / Speed = 240 km / 60 km/h = 4 hours

2. Time taken by the motorcycle to cover the distance: - Distance = 240 km - Speed = 40 km/h - Time = Distance / Speed = 240 km / 40 km/h = 6 hours

Now, let's calculate the total time:

Total time = Time taken by the car + Time taken by the motorcycle = 4 hours + 6 hours = 10 hours

Therefore, after 10 hours, the car and motorcycle will be 20 km apart from each other.

Please note that the above calculation assumes constant speeds for both the car and motorcycle throughout the entire journey.