Question

Рассеянный с улицы Бассейной, уезжая с дачи на своей "Оке", забыл ключи от городской квартиры. Сын, увидев ключи, поехал за ним в догонку на мотоцикле. Через какое время сын догонит отца, если он обнаружил ключи на веранде через 30 минут после отъезда отца? Скорость оки 80км/ч, а мотоцикла 120 км/ч.

Answer 1

1) 80 * 0,5 = 40 км проехала ока за 30 мин (0,5 ч)
2) 120 - 80 = 40 км/ч с такой скорость догоняет мотоцикл оку
3) 40 : 40 = 1 час за столько догонит сын отца

Answer 2

Problem Analysis

The problem states that a person, while leaving their country house on their "Oka" car, forgot the keys to their city apartment. Their son, upon seeing the keys, decides to chase after the person on a motorcycle. The problem asks how long it will take for the son to catch up with the person if the person discovered the keys on the veranda 30 minutes after leaving and the car's speed is 80 km/h while the motorcycle's speed is 120 km/h.

Solution

To solve this problem, we need to calculate the time it takes for the son to catch up with the person. We can do this by comparing the distances covered by the person and the son.

Let's assume that the time it takes for the son to catch up with the person is t hours.

The distance covered by the person in t hours is given by the formula: distance = speed * time.

The distance covered by the son in t hours is also given by the formula: distance = speed * time.

Since the person discovered the keys on the veranda 30 minutes after leaving, the person has already covered a distance of 80 km/h * 0.5 h = 40 km.

Therefore, the distance covered by the person in t hours is 40 km + 80 km/h * t.

The distance covered by the son in t hours is 120 km/h * t.

To find the time it takes for the son to catch up with the person, we need to solve the equation:

40 km + 80 km/h * t = 120 km/h * t.

Simplifying the equation, we get:

40 km = 40 km/h * t.

Dividing both sides of the equation by 40 km/h, we get:

t = 1 hour.

Therefore, it will take the son 1 hour to catch up with the person.

Answer

The son will catch up with the person after 1 hour.

Note: The sources provided did not contain relevant information for this specific problem.