Question

От пристани отправился теплоход со скоростью 42 км\ч.Через 5 часов от той же пристани в противоположном направлении отошел катер.Через 3 часа после выхода катера, расстояние между ним и теплоходом составило 435 км.Найдите скорость катера.

Answer 1

5+3=8 всего прошел теплоход
8*42=336 всего прошел  теплоход
435-336=99 всего прошел катер
99:3=33 скорость катера

Answer 2

Теплоход всего шел 8 часов, значит он прошел 42 х 8 = 336 км. 
Катер прошел  435 - 336 = 99 км
скорость катера 99 /  3 = 33 км/ч

Answer 3

Problem Analysis

We are given that a boat departs from a dock with a speed of 42 km/h. After 5 hours, a boat departs from the same dock in the opposite direction. After 3 hours from the departure of the second boat, the distance between the two boats is 435 km. We need to find the speed of the second boat.

Solution

Let's assume the speed of the second boat is x km/h.

The first boat travels for 5 hours at a speed of 42 km/h, so the distance covered by the first boat is 5 * 42 = 210 km.

The second boat travels for 3 hours at a speed of x km/h, so the distance covered by the second boat is 3 * x km.

The total distance between the two boats is given as 435 km.

Using the above information, we can set up the following equation:

210 + 3x = 435

Simplifying the equation:

3x = 435 - 210

3x = 225

Dividing both sides by 3:

x = 75

Therefore, the speed of the second boat is 75 km/h.

Answer

The speed of the second boat is 75 km/h.