Question

1)Прочитай задачу, сделай чертёж и реши её арифметическим способом(по действиям) Из города А в город В вышел поезд со скоростью 50км/ч. Через 12ч из города А вылетел вертолёт, скорость которого в 7 раз больше скорости поезда, и догнал поезд на половине пути от А до В. Найди расстояние межу городами. 2)Составь задачу на встречное движение с теми же данными. Срочно! 55 баллов!

Answer 1

50*12=600 км-------------- проехал поезд

50*7=350 км/час-----------скорость вертолёта

350-50=300км/ч-----------скорость сближения

600:300 = 2 часа----------время вертолета

350*2 = 700км-------------- половина пути 

700*2= 1400км ------------ расстояние между городами.

2) Не знаю... Не лезет в голову

Answer 2

Problem 1: Finding the Distance between City A and City B

To solve this problem, we will first create a diagram and then use arithmetic operations to find the distance between City A and City B.

Let's start by creating a diagram:

City A ------------------------ City B
Train (50 km/h)                Helicopter (7 * 50 km/h)

According to the problem, the train leaves City A with a speed of 50 km/h. After 12 hours, a helicopter takes off from City A, and its speed is 7 times greater than the speed of the train. The helicopter catches up with the train at the halfway point between City A and City B.

Now, let's calculate the distance between City A and City B:

1. The train travels for 12 hours at a speed of 50 km/h. Therefore, the distance covered by the train is: 12 hours * 50 km/h = 600 km.

2. Since the helicopter catches up with the train at the halfway point, the distance covered by the helicopter is also 600 km.

3. Let's assume the total distance between City A and City B is x km. Since the helicopter catches up with the train at the halfway point, the distance covered by the train is half of the total distance, which is x/2 km.

4. The helicopter's speed is 7 times greater than the speed of the train. Therefore, the speed of the helicopter is: 7 * 50 km/h = 350 km/h.

5. The time taken by the helicopter to cover the distance of x/2 km is: (x/2) km / 350 km/h = (x/700) hours.

6. The time taken by the train to cover the distance of x/2 km is: (x/2) km / 50 km/h = (x/100) hours.

7. According to the problem, the helicopter takes off 12 hours after the train. Therefore, the total time taken by the helicopter is: 12 hours + (x/700) hours.

8. The total time taken by the train is: 12 hours + (x/100) hours.

9. Since the helicopter and the train meet at the halfway point, their total travel time should be the same. Therefore, we can set up the following equation:

12 hours + (x/700) hours = 12 hours + (x/100) hours

10. Solving the equation:

(x/700) hours = (x/100) hours

Multip