Question

Два велосипедиста выехали одновременно с одного пункта в противоположних направлениях. Скорость первого - 15 км/ч, второго - в одну целую три-десятых меньше. Через сколько часов растояние между ними будет 72 км. Помогите пожалуйста, буду благодарен!

Answer 1

V-общая скорость
V1-скорость первого велосипедиста
V2-скорость второго велосипедиста
V2=1.3*V1
V=V1+V2
t=S/V
условие не верно

Answer 2

Problem Analysis

Two cyclists start simultaneously from the same point in opposite directions. The speed of the first cyclist is 15 km/h, and the speed of the second cyclist is one whole number and three-tenths less than the first cyclist's speed. We need to determine the time it takes for the distance between them to be 72 km.

Solution

Let's denote the speed of the second cyclist as x km/h. According to the problem, the speed of the second cyclist is one whole number and three-tenths less than the speed of the first cyclist. Therefore, we can write the equation:

x = 15 - 1.3

Simplifying the equation, we find:

x = 13.7 km/h

Now, we can calculate the time it takes for the distance between the two cyclists to be 72 km. We know that the distance traveled by each cyclist is equal to their speed multiplied by time. Let's denote the time as t hours. The distance traveled by the first cyclist is 15t km, and the distance traveled by the second cyclist is 13.7t km.

According to the problem, the sum of the distances traveled by both cyclists is equal to 72 km:

15t + 13.7t = 72

Simplifying the equation, we find:

28.7t = 72

Solving for t, we divide both sides of the equation by 28.7:

t = 72 / 28.7

Evaluating the expression, we find:

t ≈ 2.51 hours

Therefore, it will take approximately 2.51 hours for the distance between the two cyclists to be 72 km.

Answer

It will take approximately 2.51 hours for the distance between the two cyclists to be 72 km.