Question

Два велосипедиста выехали в разных направлениях их одного посёлка.Скорость одного-13 км/ч,а другого-17 км/ч.Через сколько часов расстояние между ними будет 90 км?(писать пример)

Answer 1

13 +17=30(км) их скорость  90:30=3(ч) через 3 часа

Answer 2

Problem Analysis

Two cyclists start from the same village and travel in opposite directions. The speed of one cyclist is 13 km/h, and the speed of the other cyclist is 17 km/h. We need to determine how many hours it will take for the distance between them to be 90 km.

Solution

To solve this problem, we can use the formula: distance = speed × time. Let's assume that the first cyclist travels for 't' hours, and the second cyclist travels for 't' hours as well. The distance covered by the first cyclist is then 13t km, and the distance covered by the second cyclist is 17t km.

Since they are traveling in opposite directions, the total distance between them is the sum of the distances covered by each cyclist. Therefore, the equation becomes:

13t + 17t = 90

Simplifying the equation:

30t = 90

Dividing both sides of the equation by 30:

t = 3

Therefore, it will take 3 hours for the distance between the two cyclists to be 90 km.

Answer

It will take 3 hours for the distance between the two cyclists to be 90 km.

Explanation

When the first cyclist travels for 3 hours at a speed of 13 km/h, they will cover a distance of 13 km/h × 3 h = 39 km. Similarly, when the second cyclist travels for 3 hours at a speed of 17 km/h, they will cover a distance of 17 km/h × 3 h = 51 km. The sum of these distances is 39 km + 51 km = 90 km, which is the required distance between them.