Question

Света и Миша едут на велосипедах со скоростью 210м/мин, а Игорь идёт со скоростью 70м/мин. Они находятся на расстоянии 8 км 400 м друг от друга. Через какое время расстояние между ребятами станет 4 км 200 м?

Answer 1

Problem Analysis

We have three individuals: Sveta and Misha, who are riding bicycles at a speed of 210 m/min, and Igor, who is walking at a speed of 70 m/min. The initial distance between Sveta and Misha and Igor is 8 km 400 m. We need to determine how long it will take for the distance between Sveta and Misha to become 4 km 200 m.

Solution

To solve this problem, we can use the formula: distance = speed × time. Let's denote the time it takes for the distance between Sveta and Misha to become 4 km 200 m as t.

The distance traveled by Sveta and Misha in time t is given by: distance = speed × time. Therefore, the distance traveled by Sveta and Misha is 210t.

The distance traveled by Igor in time t is given by: distance = speed × time. Therefore, the distance traveled by Igor is 70t.

The initial distance between Sveta and Misha and Igor is 8 km 400 m. Therefore, the equation becomes: (8 km 400 m) - (210t) = (70t).

To solve for t, we can convert the distances to meters and solve the equation.

Calculation

Let's convert the distances to meters: - Initial distance: 8 km 400 m = 8,400 m - Final distance: 4 km 200 m = 4,200 m

Now, let's solve the equation: 8,400 - 210t = 70t.

Simplifying the equation: - 8,400 = 280t - Dividing both sides by 280: t = 30

Therefore, it will take 30 minutes for the distance between Sveta and Misha to become 4 km 200 m.

Answer

The distance between Sveta and Misha will become 4 km 200 m after 30 minutes.