Question

Внучка с собачкой увидела своего дедушку на расстоянии 300 м от себя и побежала ему на встречу . дедушка в тот же момент также увидел свою внучку и направился к ней . собачка всё время бегала между дедушкой и внучкой до тех пор, пока они не встретились. Какой путь пробежала собачка, если её скорость 30 км/ч, скорость дедушки 3 км/ч а скорость внучки 6 км/ч

Answer 1

1. 300м=0,3км. Найдем время, через которое внучка встретиться с дедушкой:
0,3/(3+6)=0,3/9=0,1/3=1/30.
2. Зная скорость собачки и то, что она бежала 1/30 часа, найдем ее путь: 30*(1/30)=1км.

1км.

Answer 2

Calculating the Dog's Path

To calculate the distance the dog ran, we can use the formula: distance = speed × time

First, let's calculate the time it took for the grandfather and the granddaughter to meet. We can use the formula: time = distance / speed

The dog's speed is 30 km/h, the grandfather's speed is 3 km/h, and the granddaughter's speed is 6 km/h.

Time Calculation

The time it took for the grandfather and the granddaughter to meet can be calculated using the formula: time = distance / relative speed

The relative speed of the grandfather and the granddaughter is the sum of their speeds, as they are moving towards each other.

The relative speed = 3 km/h + 6 km/h = 9 km/h

Using the formula: time = 300 m / (9 km/h) time = (300 m / 1000) / (9/60) time = 0.3 km / (9/60) time = 0.3 km / 0.15 h time = 2 hours

So, it took 2 hours for the grandfather and the granddaughter to meet.

Distance Calculation

Now, let's calculate the distance the dog ran during this time.

The dog's speed is 30 km/h, and it ran for 2 hours.

Using the formula: distance = speed × time distance = 30 km/h × 2 h distance = 60 km

Therefore, the dog ran a distance of 60 kilometers while the grandfather and the granddaughter were meeting.