Question

Решить задачу Велосипедист ехал 2 часа по проселочной дороге и 1 час по шоссе.Всего он проехал 28км.С какой скоростью велосипедист ехал по проселочной дороге и с какой по шоссе,если известно,что скорость по шоссе была на 4 км/ч больше,чем по проселочной дороге?

Answer 1

Пусть х- скорость велосипедиста по просел. дороге,тогда скорость по шоссе = х+4. Составляем и решаем уравнение: 2х +(х+4)= 28, 3х=28-4, 3х=24,     х=24/3, х=8.Так как за х брали скорость по просел. дороге, получили, что скорость по прос дороге равна 8, а по шоссе х+4, то есть 8+4=12. Ответ: 8км/ч, 12км/ч

Answer 2

Problem Analysis

To solve this problem, we need to find the speed at which the cyclist traveled on the dirt road and the highway. We know that the cyclist traveled for 2 hours on the dirt road and 1 hour on the highway, covering a total distance of 28 km. Additionally, we are given that the speed on the highway was 4 km/h greater than the speed on the dirt road.

Solution

Let's denote the speed on the dirt road as x km/h. Then the speed on the highway would be (x + 4) km/h.

We can use the formula: Distance = Speed × Time

For the time spent on the dirt road: 28 = 2x [[1 #1]]

For the time spent on the highway: 28 = (x + 4) × 1 [[1 #1]]

Now, we can solve these equations to find the values of x and (x + 4).

Calculation

From the first equation: 2x = 28 x = 14 [[3 #1]]

From the second equation: (14 + 4) = 18 [[3 #1]]

Answer

So, the cyclist traveled at a speed of 14 km/h on the dirt road and at a speed of 18 km/h on the highway.