Question

Из одного города в другой расстояние между которыми равно 240 км,одновременно выехали легковой автомобиль и грузовик,известно что скорость автомобиля на 40 км\ч больше.Вычислите на сколько часов больше затратил на дорогу грузовик,если легковой автомобиль был в пути 3 часа.ПОЖАЛУЙСТА ПИШИТЕ,СРОЧНО НАДО

Answer 1

1)240:3=80(км/ч)скорость автомобиля
2)80-40=40(км/ч)скорость грузовика
3)240:40=6(часов)
4)6-3=3(часа)
Ответ:на 3 часа граузовик ехал дольше чем легковой автомобиль
                            НАВЕРНО ТАК

Answer 2

Problem Analysis

We are given that the distance between two cities is 240 km. A car and a truck start simultaneously from the same city, and it is known that the car's speed is 40 km/h faster than the truck's speed. We need to calculate how many additional hours the truck spent on the road if the car was on the road for 3 hours.

Solution

Let's assume the speed of the truck is x km/h. Since the car's speed is 40 km/h faster, the car's speed is x + 40 km/h.

We know that distance = speed × time. For the car, the distance traveled is (x + 40) × 3 km, and for the truck, the distance traveled is x × t km.

Since the total distance between the two cities is 240 km, we can write the equation:

(x + 40) × 3 + x × t = 240

Simplifying the equation, we get:

3x + 120 + xt = 240

Now, we need to solve this equation to find the value of t.

Let's solve the equation step by step:

1. Distribute the 3 to x and 40:

3x + 120 + xt = 240

2. Combine like terms:

3x + xt + 120 = 240

3. Rearrange the terms:

xt + 3x = 240 - 120

xt + 3x = 120

4. Factor out x:

x(t + 3) = 120

5. Divide both sides by (t + 3):

x = 120 / (t + 3)

Now, we have the value of x in terms of t. We can substitute this value back into the equation to find the value of t.

Let's solve the equation using the given information.

Calculation

Given that the car was on the road for 3 hours, we can substitute t = 3 into the equation:

x = 120 / (3 + 3)

Simplifying:

x = 120 / 6

x = 20

Therefore, the speed of the truck is 20 km/h.

Now, we can calculate the time spent by the truck on the road. Since the distance traveled by the truck is 240 km and the speed is 20 km/h, we can use the formula time = distance / speed:

time = 240 / 20

time = 12 hours

Since the car was on the road for 3 hours, the truck spent 12 - 3 = 9 hours more on the road.

Answer

The truck spent 9 hours more on the road than the car.