Question

два мальчика идут навстречу друг другу. сейчас между ними 12 км. скорость одного из них составляет 2/3 скорости другого. найдите скорость движения каждого мальчика, если известно, что они встретятся через 1,5 ч.

Answer 1

х- скорость 1го мальчика

2/3х - скорость 2го

1,5(х+2/3х)=12

1,5х+х=12

2,5х=12

х=4,8 (км/ч) - скорость1го мальчика

4,8*2/3=24/5*2/3=16/5=3,2 (км/ч) - скорость 2го мальчика

Answer 2

12:1,5=8 км/ч  скорость сближения,

х+2/3х=8
5/3х=8
х=8:5/3
х=4,8км/ч скорость первого мальчика
8-4,8=3,2км/ч скорость второго мальчика

Answer 3

Problem Analysis

Two boys are walking towards each other, and the distance between them is 12 km. The speed of one of the boys is 2/3 of the speed of the other boy. We need to find the speed of each boy if they meet after 1.5 hours.

Solution

Let's assume the speed of the slower boy is x km/h. Then the speed of the faster boy will be (2/3)x km/h.

We can use the formula distance = speed × time to find the distance traveled by each boy in 1.5 hours.

For the slower boy: distance = speed × time 12 km = x km/h × 1.5 h

For the faster boy: distance = speed × time 12 km = (2/3)x km/h × 1.5 h

Now we can solve these equations to find the values of x and (2/3)x.

Calculation

Let's solve the equations:

For the slower boy: 12 km = x km/h × 1.5 h Divide both sides by 1.5: 8 km/h = x km/h

For the faster boy: 12 km = (2/3)x km/h × 1.5 h Divide both sides by 1.5: 8 km = (2/3)x km/h × 1.5 h Multiply both sides by 3/2: 12 km = 2x km/h Divide both sides by 2: 6 km/h = x km/h

So, the speed of the slower boy is 8 km/h and the speed of the faster boy is (2/3) × 8 km/h = 16/3 km/h.

Answer

The speed of the slower boy is 8 km/h and the speed of the faster boy is 16/3 km/h.

Note: The above solution assumes that the boys are walking at a constant speed. If there are any other factors involved, such as changes in speed or breaks, the solution may vary.