Question

С двух железнодорожных станций,расстояние между которыми 124 км,одновременно в противоположенных направлениях отправились два поезда,Через 1 ч 45 мин расстояние между поездами стало равно 369 км. Отношение скорости первого поезда к скорости второго равно 3:4. Найдите скорость каждого поезда.

Answer 1

1ч45мин=1,75ч

369-124=245(км) - расстояние проехали оба поезда за 1,75час

245:1,75=140(км/ч) - скорость сближения

4+3=7 - частей составляют 140км/ч

140:7=20(км/ч) - 1часть

20*3=60(км/ч) - скорость І поезда

20*4=80(км/ч) - скорость ІІ поезда

Answer 2

Problem Analysis

We are given that two trains start simultaneously from two railway stations, and after 1 hour and 45 minutes, the distance between them is 369 km. The ratio of the speed of the first train to the speed of the second train is 3:4. We need to find the speed of each train.

Solution

Let's assume the speed of the first train is 3x km/h and the speed of the second train is 4x km/h.

We know that distance = speed × time.

After 1 hour and 45 minutes (which is 1.75 hours), the distance between the trains is 369 km. So, we can set up the following equation:

(3x + 4x) × 1.75 = 369

Simplifying the equation:

7x × 1.75 = 369

12.25x = 369

x = 369 / 12.25

x ≈ 30

Therefore, the speed of the first train is 3x ≈ 3 × 30 = 90 km/h, and the speed of the second train is 4x ≈ 4 × 30 = 120 km/h.

Answer

The speed of the first train is approximately 90 km/h, and the speed of the second train is approximately 120 km/h.