Question

Из двух посёлков расстояние между которыми 78 км одновременно навстречу друг другу выехали два велосипедиста скорость первого 18 км ч а второго на 3 км ч больше через сколько часов они встретятся А через 4 часа Б через 2 часа В через 3 часа Г через 1 час

Answer 1

1) 18+3=21(км/ч)-скорость второго
2) 18+21=39 (км/ч)-общая скорость
3) 78:39=2(ч)
Ответ: велосипедисты встретятся через 2 часа

ОТВЕТ: Б.

Answer 2

Problem Analysis

We are given that two cyclists start simultaneously from two villages that are 78 km apart. The first cyclist has a speed of 18 km/h, while the second cyclist has a speed that is 3 km/h faster than the first cyclist. We need to determine how long it will take for the two cyclists to meet.

Solution

Let's assume that the time it takes for the two cyclists to meet is t hours.

The distance covered by the first cyclist in t hours is given by 18t km.

The distance covered by the second cyclist in t hours is given by (18 + 3)t km.

Since they are traveling towards each other, the sum of the distances covered by both cyclists should be equal to the total distance between the villages, which is 78 km.

Therefore, we can write the equation:

18t + (18 + 3)t = 78

Simplifying the equation:

21t = 78

Solving for t:

t = 78 / 21

Evaluating the expression:

t ≈ 3.714

Therefore, it will take approximately 3.714 hours for the two cyclists to meet.

Answer

The two cyclists will meet approximately after 3.714 hours.