Question

Из А В Б одновременно выехали два автомобилиста первый проехал с постоянной скоростью весь путь второй проехал Первую половину пути со скоростью меньшей скорости первого на 12 км в час а вторую половину пути со скоростью 90 километров час в результате чего прибыл в B одновременно с первым автомобилем Найдите скорость первого автомобиля

Answer 1

Слишком слооооожна.Сорян.

Answer 2

Problem Analysis

We are given that two drivers, A and B, simultaneously set off from point A to point B. The first driver travels the entire distance at a constant speed, while the second driver travels the first half of the distance at a speed 12 km/h slower than the first driver and the second half of the distance at a speed of 90 km/h. We need to find the speed of the first driver.

Solution

Let's assume the distance from point A to point B is D km.

The first driver travels the entire distance at a constant speed, which we will call V km/h.

The second driver travels the first half of the distance at a speed 12 km/h slower than the first driver, so their speed is (V - 12) km/h. The time taken to travel the first half of the distance is D/2 / (V - 12) hours.

The second driver travels the second half of the distance at a speed of 90 km/h. The time taken to travel the second half of the distance is D/2 / 90 hours.

Since both drivers arrived at point B simultaneously, the total time taken by both drivers must be the same. Therefore, we can set up the following equation:

D/2 / (V - 12) = D/2 / 90

To solve for V, we can cross-multiply and simplify the equation:

D/2 * 90 = D/2 * (V - 12)

Canceling out the common terms:

90 = V - 12

Solving for V:

V = 90 + 12

V = 102 km/h

Answer

The speed of the first driver is 102 km/h.