Question

СРОЧНО - ПРИСРОСРОЧНОСкорость течения реки равна 2 км/ч. Два катера отошли от одной пристани в противоположных направлениях. Собственная скорость катера, движущегося по течению реки, равна 20 1/2 км/ч, а собственного скорость второго катера-21 1/3 км/ч. На каком расстоянии друг от друга они будут через 5 ч.

Answer 1

1) 20 1/2+2=22 1/2 км/ч - скорость катера по течению
2) 21 1/3-2=19 1/3 км/ч - скорость катера против течения
3) 22 1/2+19 1/3=41 5/6 км/ч скорость удаления
4) 41 5/6·5=1255/6=209 1/6км - расстояние между катерами через 5ч.

Answer 2

Problem Analysis

We are given the following information: - The speed of the river current is 2 km/h. - Two boats are moving in opposite directions from the same dock. - The speed of the first boat relative to the river current is 20 1/2 km/h. - The speed of the second boat relative to the river current is 21 1/3 km/h. - We need to find the distance between the two boats after 5 hours.

To solve this problem, we can use the formula: distance = (speed of boat 1 + speed of boat 2) * time.

Calculation

Let's calculate the distance between the two boats after 5 hours.

The speed of the first boat relative to the river current is 20 1/2 km/h. Since the river current is flowing in the same direction as the first boat, we need to subtract the speed of the river current from the speed of the boat to get the effective speed of the boat: 20 1/2 km/h - 2 km/h = 18 1/2 km/h.

The speed of the second boat relative to the river current is 21 1/3 km/h. Since the river current is flowing in the opposite direction to the second boat, we need to add the speed of the river current to the speed of the boat to get the effective speed of the boat: 21 1/3 km/h + 2 km/h = 23 1/3 km/h.

Now, we can calculate the distance between the two boats after 5 hours using the formula: distance = (speed of boat 1 + speed of boat 2) * time.

Substituting the values: distance = (18 1/2 km/h + 23 1/3 km/h) * 5 hours

To simplify the calculation, we can convert the mixed fractions to improper fractions: distance = (37/2 km/h + 70/3 km/h) * 5 hours

Now, let's calculate the distance: distance = (37/2 + 70/3) * 5 distance = (111/6 + 140/6) * 5 distance = 251/6 * 5 distance = 1255/6 km

Therefore, the distance between the two boats after 5 hours is 1255/6 km.

Answer

The distance between the two boats after 5 hours is 1255/6 km.

Note: The answer is provided in fractional form as it is the exact result of the calculation.