Question

Велосипед ехал 3 ч со скоростью 18 км/ч. Обратно он поехал другой дорогой,которая была длинее первой на 9 км,но и скорость велосипедиста на обратном пути была на 3км /ч больше.Сколько времени велосипед затратил на обратную дорогу?

Answer 1

3*18=54км это расстояние 1 дорого, 54+9=63 это расстояние 2 дороги,18+3=21 это его 2 скорость,63:21=3 часа на обратную дорогу

Answer 2

Problem Analysis

We are given that a cyclist traveled for 3 hours at a speed of 18 km/h. On the return journey, the cyclist took a different route that was 9 km longer and traveled at a speed 3 km/h faster. We need to determine how much time the cyclist spent on the return journey.

Solution

To solve this problem, we can use the formula: time = distance / speed.

Let's calculate the distance traveled on the first leg of the journey using the formula: distance = speed * time. - Speed = 18 km/h - Time = 3 hours

Distance on the first leg = 18 km/h * 3 hours = 54 km.

Now, let's calculate the speed on the return journey. We are given that the speed on the return journey is 3 km/h faster than the speed on the first leg. - Speed on the first leg = 18 km/h - Speed on the return journey = 18 km/h + 3 km/h = 21 km/h.

Next, let's calculate the distance on the return journey. We are given that the return journey is 9 km longer than the first leg. - Distance on the return journey = Distance on the first leg + 9 km = 54 km + 9 km = 63 km.

Finally, let's calculate the time spent on the return journey using the formula: time = distance / speed. - Distance on the return journey = 63 km - Speed on the return journey = 21 km/h

Time spent on the return journey = 63 km / 21 km/h = 3 hours.

Therefore, the cyclist spent 3 hours on the return journey.

Answer

The cyclist spent 3 hours on the return journey.