Question

Из одного пункта в противоположных направлениях вышли два пешехода. Через 1.2 часа между ними стало 156 км. Какова скорость второго и первого, если скорость первого в 1.6 раза больше второго?

Answer 1

(x+1.6x)*1.2= 156
2.6x*1.2=156
x=
156:(2.6*1.2)=50
50*1.6=80
x1=80
x2=50

Answer 2

Problem Analysis

We have two pedestrians who started walking from the same point in opposite directions. After 1.2 hours, the distance between them is 156 km. The speed of the first pedestrian is 1.6 times greater than the speed of the second pedestrian. We need to find the speeds of both pedestrians.

Solution

Let's assume the speed of the second pedestrian is x km/h. Since the speed of the first pedestrian is 1.6 times greater, the speed of the first pedestrian is 1.6x km/h.

We can use the formula distance = speed × time to find the distances covered by both pedestrians in 1.2 hours.

For the first pedestrian: distance1 = (1.6x) × 1.2

For the second pedestrian: distance2 = x × 1.2

According to the problem, the sum of the distances covered by both pedestrians is 156 km: distance1 + distance2 = 156

Now we can substitute the values of distance1 and distance2 into the equation and solve for x.

Calculation

Let's solve the equation distance1 + distance2 = 156 for x:

1.6x × 1.2 + x × 1.2 = 156

Simplifying the equation:

1.92x + 1.2x = 156

3.12x = 156

Dividing both sides by 3.12:

x = 156 / 3.12

x = 50

So, the speed of the second pedestrian is 50 km/h, and the speed of the first pedestrian is 1.6 times greater, which is 1.6 × 50 = 80 km/h.

Answer

The speed of the second pedestrian is 50 km/h, and the speed of the first pedestrian is 80 km/h.