Question

В полдень от пристани отошел теплоход со скоростью 16км/ч. Через 3 ч от той же пристани в том же направлении отошел другой теплоход и через 12 ч догнал первый. Вычисли скорость второго теплохода.

Answer 1

1) первый всего потратил времени 15 часов, поэтому вычислим его пройденный путь 15*12=240
2) второй проплыл такое же расстояние, потому что они он догнал первого, тогда 12*скорость=240, отсюда скорость = 20км/ч

Answer 2

Problem Analysis

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

Solution

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

The first steamboat travels for 3 hours before the second steamboat starts. So, the distance covered by the first steamboat in 3 hours is 16 km/h * 3 h = 48 km.

When the second steamboat starts, the first steamboat is already 48 km ahead. The second steamboat catches up with the first steamboat after 12 hours. During this time, the first steamboat also travels for 12 hours.

Let's calculate the distance covered by the first steamboat in 12 hours: 16 km/h * 12 h = 192 km.

Since the second steamboat catches up with the first steamboat, the distance covered by the second steamboat in 12 hours is also 192 km.

Now, let's set up an equation to find the speed of the second steamboat:

Distance covered by the second steamboat = Speed of the second steamboat * Time taken by the second steamboat

192 km = x km/h * 12 h

Simplifying the equation, we get:

192 km = 12x km/h

Dividing both sides of the equation by 12, we get:

16 km = x km/h

Therefore, the speed of the second steamboat is 16 km/h.

Answer

The speed of the second steamboat is 16 km/h.