Question

Автомобиль из А в В ехал со скоростью 50 км/ч,а обратно 30км/с.Какова его средняя скорость?

Answer 1

Наверное опечатка и не 30км\с- а 30км\ч

Время пути из А в В равно АВ/50 ч. время пути из В в А равно AB/30 ч. Тогда средняя скорость равна весь путь : на все время, єто
$(AB+AB):(\frac{AB}{50}+\frac{AB}{30})=$
$2AB:\frac{(30+50)AB}{50*30}=$
$\frac{2AB*30*50}{80AB}=37.5$
ответ: 37.5 км\ч

Answer 2

Ответ : 40 км/час
реш. на фото

Answer 3

Calculation of Average Speed

To calculate the average speed of a car traveling from point A to point B and back, we need to consider the distances and speeds for each leg of the journey.

Let's assume the distance from point A to point B is the same as the distance from point B to point A.

Given: - Speed from A to B: 50 km/h - Speed from B to A: 30 km/h

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

Average Speed = Total Distance / Total Time

Since the distance from A to B is the same as the distance from B to A, we can consider the total distance as twice the distance from A to B.

Let's assume the distance from A to B is d.

The time taken to travel from A to B is given by:

Time from A to B = Distance / Speed = d / 50

The time taken to travel from B to A is given by:

Time from B to A = Distance / Speed = d / 30

The total time for the round trip is the sum of the time from A to B and the time from B to A:

Total Time = (d / 50) + (d / 30)

Substituting the values into the formula for average speed:

Average Speed = (2d) / [(d / 50) + (d / 30)]

Simplifying the equation:

Average Speed = (2d) / [(3d + 5d) / 150] = 300d / 8d = 37.5 km/h

Therefore, the average speed of the car for the round trip is 37.5 km/h.