Question

мотоцикл из пункта а в пункт в ехал со скоростью v1 =60 км/ч. На обратном пути он половину времент ехал со скоростью v2 =50 км/ч, а оставшийся участок со скоростью v3. найдите эту скорость, если средняя скорость этой поездки оказалось равна 60 км/ч

Answer 1

Ответ:

60×3=180 сумма всех скоростей

180-(60+50)=70

Объяснение:

решал сам

Answer 2

Problem Analysis

We are given that a motorcycle travels from point A to point B at a speed of v1 = 60 km/h. On the return trip, the motorcycle travels half the time at a speed of v2 = 50 km/h, and the remaining distance at an unknown speed v3. We need to find the value of v3 if the average speed for the entire trip is 60 km/h.

Solution

To find the value of v3, we can use the formula for average speed:

Average Speed = Total Distance / Total Time

Let's assume the distance from point A to point B is D. Since the motorcycle travels at a speed of v1 = 60 km/h for the entire distance on the forward trip, the time taken for the forward trip is:

Time1 = D / v1

On the return trip, the motorcycle travels half the time at a speed of v2 = 50 km/h. Therefore, the time taken for this part of the trip is:

Time2 = (1/2) * (D / v2)

The remaining distance is also D, and the time taken to cover this distance at speed v3 is:

Time3 = D / v3

The total time for the entire trip is the sum of Time1, Time2, and Time3:

Total Time = Time1 + Time2 + Time3

Since the average speed for the entire trip is given as 60 km/h, we can write:

60 = (Total Distance) / (Total Time)

Substituting the values of Total Distance and Total Time, we get:

60 = (2D) / (Time1 + Time2 + Time3)

Now, we can substitute the values of Time1, Time2, and Time3 in terms of D and the given speeds v1, v2, and v3:

60 = (2D) / ((D / v1) + (1/2) * (D / v2) + (D / v3))

Simplifying the equation, we get:

60 = (2 * v1 * v2 * v3) / (v1 * v2 + v1 * v3 + v2 * v3)

Now, we can solve this equation to find the value of v3.

Calculation

Substituting the given values v1 = 60 km/h and v2 = 50 km/h into the equation, we get:

60 = (2 * 60 * 50 * v3) / (60 * 50 + 60 * v3 + 50 * v3)

Simplifying further, we have:

60 = (6000 * v3) / (3000 + 110 * v3)

Cross-multiplying, we get:

360000 + 6600 * v3 = 6000 * v3

Rearranging the equation, we have:

600 * v3 = 360000

Dividing both sides by 600, we get:

v3 = 600

Therefore, the value of v3 is 600 km/h.

Answer

The speed v3 of the motorcycle on the remaining distance is 600 km/h.