Question

Автомобиль выехал с постоянной скоростью 56 км/ч из города А в город В, расстояние между которыми равно 280 км. Одновременно с ним из города С в город В, расстояние между которыми равно 369 км, с постоянной скоростью выехал мотоциклист. По дороге он сделал остановку на 30 минут. В результате автомобиль и мотоцикл прибыли в город В одновременно. Найдите скорость мотоциклиста. Ответ дайте в км/ч

Answer 1

                S             V              t
Автом.   280км      56км/ч     280/56 = 5часов
А-В 
мотоц.   369км       хкм/ч       369/х
С-В 
369/х + 1/2= 5
369/х= 4 1/2
369/х =  9/2
х = 369*2 : 9 =82 (км/ч) - скорость мотоциклиста

Answer 2

Problem Analysis

We are given that a car travels from city A to city B at a constant speed of 56 km/h, a distance of 280 km. At the same time, a motorcyclist travels from city C to city B, a distance of 369 km, at a constant speed. The motorcyclist makes a 30-minute stop along the way. We need to find the speed of the motorcyclist in km/h.

Solution

To find the speed of the motorcyclist, we can use the formula:

Speed = Distance / Time

Let's calculate the time it takes for the car to travel from city A to city B:

Time taken by the car = Distance / Speed = 280 km / 56 km/h = 5 hours

Since the car and the motorcyclist arrive in city B at the same time, the motorcyclist's total travel time should be the same as the car's travel time minus the 30-minute stop:

Motorcyclist's travel time = Car's travel time - 30 minutes = 5 hours - 0.5 hours = 4.5 hours

Now, we can calculate the speed of the motorcyclist using the formula:

Speed = Distance / Time = 369 km / 4.5 hours

Calculation

Let's calculate the speed of the motorcyclist:

Speed = 369 km / 4.5 hours = 82 km/h

Therefore, the speed of the motorcyclist is 82 km/h.

Answer

The speed of the motorcyclist is 82 km/h.