Question

Реши задачу.В полдень от пристани отошел теплоход со скоростью 16 км/ч. Через 3 ч вслед ему отошел другой теплоход и через 12 ч догнал первый. С какой скоростью двигался второй теплоход

Answer 1

1) 3 + 12 = 15(ч) был в пути 1-ой теплоход
2) 16 * 15 = 240(км) - расстояние, пройденное 1-ым теплоходом
3) 2-ой теплоход был в пути только 12 часов, и за это время он также прошёл 240км (это пояснение лично для тебя, чтобы было понятно) .Это можно не писать.
    240 : 12 = 20(км/ч)
Ответ: 20км/ч - скорость 2-ого теплохода.

Answer 2

Problem Analysis

We are given that a ship departs from a pier at noon with a speed of 16 km/h. Another ship departs after 3 hours and catches up with the first ship after 12 hours. We need to find the speed of the second ship.

Solution

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

The first ship has been traveling for 12 hours when the second ship catches up. During this time, the first ship has covered a distance of 16 km/h * 12 h = 192 km.

The second ship has been traveling for 12 - 3 = 9 hours when it catches up with the first ship. During this time, the second ship has covered a distance of x km/h * 9 h = 9x km.

Since both ships have covered the same distance when the second ship catches up, we can set up the equation:

192 km = 9x km

Solving for x, we get:

x = 192 km / 9 h x = 21.33 km/h

Therefore, the speed of the second ship is approximately 21.33 km/h.

Answer

The second ship was moving at a speed of approximately 21.33 km/h.