Question

1. Из деревни А в деревню В одновременно вышли два друга. Первый друг шел весь путь с постоянной скоростью. Второй друг первую половину пути шел со скоростью, на 15 м/мин меньшей скорости первого друга, а вторую половину -со скоростью 50м/мин. В итоге в пункте назначения оказались одновременно. Найдите скорость первого друга. Ответ запишите в м/мин.

Answer 1

Пусть скорость первого =х на первом отрезке  на втором равна тоже х
тогда 50+х-15=2х
х=35 м/ мин  скорость первого

Answer 2

Calculating the Speed of the First Friend

To find the speed of the first friend, we can use the formula for average speed, which is total distance divided by total time. Let's denote the speed of the first friend as x.

The total distance is the same for both friends, as they both traveled from village A to village B. The total time for the first friend is the entire journey, while for the second friend, it's the sum of the times taken for the first and second halves of the journey.

Calculating the Time for the Second Friend

The time taken by the second friend for the first half of the journey can be calculated using the formula time = distance / speed. The distance for the first half is half of the total distance, and the speed is 15 m/min less than the speed of the first friend.

The time taken by the second friend for the second half of the journey can also be calculated using the same formula, with the distance being the remaining half of the total distance and the speed being 50 m/min.

Setting Up the Equations

We can set up the equations based on the information provided and solve for the speed of the first friend.

Let's denote the total distance as d and the speed of the first friend as x.

The time taken by the second friend for the first half of the journey can be expressed as: time1 = d / (x - 15)

The time taken by the second friend for the second half of the journey can be expressed as: time2 = d / 50

The total time taken by the second friend is the sum of time1 and time2.

Solving for the Speed of the First Friend

By setting up the equations and solving for the speed of the first friend, we can find the value of x in m/min.

Let's proceed with the calculations.