Question

От 2 пристаней, находящихся на расстоянии 90км,отошли одновременно навстречу друг другу два теплохода. Скорость о одного из них 24км/час,скорость другого 21км/час.через сколько часов теплоходы встретились?Реши задачу,составив выражение.

Answer 1

90км :(24+21)=2час
общ скорость = 24+21
расстояние : на скорость = время

Answer 2

1) 24 + 21 = 45 км/ч - скорость сближения
2) 90 : 45 = 2 ч - через столько они встретились.

Выражение :
90 : (24 + 21) = t

Answer 3

Problem Analysis

We have two steamboats that depart simultaneously from two different piers, which are 90 km apart. The first steamboat has a speed of 24 km/h, and the second steamboat has a speed of 21 km/h. We need to determine how many hours it will take for the steamboats to meet.

Solution

Let's assume that it takes t hours for the steamboats to meet. During this time, the first steamboat will travel a distance of 24t km, and the second steamboat will travel a distance of 21t km. Since they are moving towards each other, the sum of their distances traveled should be equal to the distance between the piers, which is 90 km.

We can set up the following equation to solve for t:

24t + 21t = 90

Simplifying the equation:

45t = 90

Dividing both sides by 45:

t = 2

Therefore, it will take 2 hours for the steamboats to meet.

Answer

The steamboats will meet after 2 hours.