Question

За 3 ч автобус преодолевает такое же расстояние, какое проедет поезд - за 2 ч. Туристы ехали 4 ч на автобусе и 3 ч на поезде,а всего они проехали 408 км. Найдите скорость автобуса и скорость поезда.(Напишите только систему,я сам решу).

Answer 1

х км/ч - скорость автобуса

у км/ч - скорость поезда

3х=2у

х=2у/3

4х+3у=408

4(2у/3)+3у=408,общий знаменатель 3

8у+9у=1224

у=72(км/x) - cкорость поезда

72*2:3=48(км/ч) - скорость автобуса

Answer 2

скорость автобуса Х км/ч -3 ч

скорость поезда У км/ч -4 ч

3*х=4*у

турист |4 часа на автобусе 4*х |   Всего 408 км.

           |3 часа на поезде 3*у   | 

ИТОГО: два уравнения

4*х+3у=408

х=2у/3

 

(выразишь сначала У, потом найдешь Х.) 

Answer 3

Problem Analysis

We are given that a bus takes 3 hours to travel the same distance that a train covers in 2 hours. The tourists traveled for 4 hours on the bus and 3 hours on the train, covering a total distance of 408 km. We need to find the speed of the bus and the speed of the train.

Solution

Let's assume the speed of the bus is x km/h and the speed of the train is y km/h.

We can use the formula distance = speed × time to create a system of equations based on the given information.

For the bus: x × 3 = distance (equation 1)

For the train: y × 2 = distance (equation 2)

We also know that the total distance covered by the tourists is 408 km: x × 4 + y × 3 = 408 (equation 3)

Now we can solve this system of equations to find the values of x and y.

Solution Steps

1. Rewrite equation 1 as distance = x × 3. 2. Rewrite equation 2 as distance = y × 2. 3. Substitute these expressions for distance into equation 3: - x × 4 + y × 3 = x × 3 - Simplify the equation: 4x + 3y = 3x - Rearrange the equation: 4x - 3x = -3y - Simplify further: x = -3y 4. Substitute the value of x from equation 3 into equation 1: - distance = (-3y) × 3 - Simplify: distance = -9y 5. Substitute the value of x from equation 3 into equation 2: - distance = y × 2 - Simplify: distance = 2y 6. Since both equations 4 and 5 represent the same distance, we can equate them: - -9y = 2y - Simplify: -11y = 0 - Solve for y: y = 0 7. Substitute the value of y into equation 2 to find x: - 0 × 2 = distance - Simplify: distance = 0 - Since the distance cannot be zero, there is no valid solution for x. 8. Therefore, there is no valid solution for the speed of the bus and the speed of the train.

Answer

Based on the given information, there is no valid solution for the speed of the bus and the speed of the train.