Question

Помогите пожалуйста Расстояние между двумя пристанями равно 81,6 км. Из них одновременно навстречу друг другу вышли две лодки, скорости которых в стоячей воде равны. Через 1,7 ч. лодки встретились. Скорость течения реки равна 2 км/ч. Скорость лодки в стоячей воде равна ... км/ч. Сколько километров до места встречи пройдёт лодка, плывущая по течению? ... км. Сколько километров до места встречи пройдёт лодка, плывущая против течения? ... км.

Answer 1

Ответ:

X-собственная скорость

1.7(х+2)+1.7(х-2)=81.6

1.7х+3.4+1.7х-3.4=81.6

3.4х=81.6

х=24- собственная скорость

По течению-1.7×26=44.2

Против- 1.7×22=37.4

Объяснение:

Answer 2

Problem Analysis

We have two boats traveling towards each other from two different ports. The distance between the ports is 81.6 km. The boats meet after 1.7 hours. The speed of the river current is 2 km/h. We need to find the speed of the boats in still water and calculate the distance each boat will travel before they meet.

Let's assume the speed of each boat in still water is x km/h.

Solution

To solve this problem, we can use the formula:

Distance = Speed × Time

Let's calculate the distance each boat will travel before they meet.

The first boat is traveling towards the second boat, so its effective speed will be the sum of its speed in still water and the speed of the river current. The second boat is traveling against the river current, so its effective speed will be the difference between its speed in still water and the speed of the river current.

Let's calculate the distance each boat will travel before they meet.

Distance Traveled by the First Boat

The first boat is traveling towards the second boat, so its effective speed will be the sum of its speed in still water and the speed of the river current.

Effective speed of the first boat = Speed of the first boat in still water + Speed of the river current

The time taken by the first boat to meet the second boat is given as 1.7 hours.

Distance traveled by the first boat = Effective speed of the first boat × Time taken

Distance Traveled by the Second Boat

The second boat is traveling against the river current, so its effective speed will be the difference between its speed in still water and the speed of the river current.

Effective speed of the second boat = Speed of the second boat in still water - Speed of the river current

The time taken by the second boat to meet the first boat is also given as 1.7 hours.

Distance traveled by the second boat = Effective speed of the second boat × Time taken

Calculation

Let's substitute the given values into the formulas and calculate the distances.

Distance traveled by the first boat = (x + 2) × 1.7

Distance traveled by the second boat = (x - 2) × 1.7

Since the total distance between the two ports is 81.6 km, the sum of the distances traveled by the two boats should be equal to 81.6 km.

Distance traveled by the first boat + Distance traveled by the second boat = 81.6

Substituting the formulas for the distances:

(x + 2) × 1.7 + (x - 2) × 1.7 = 81.6

Now we can solve this equation to find the value of x.

Solving the Equation

Let's simplify the equation and solve for x.

(x + 2) × 1.7 + (x - 2) × 1.7 = 81.6

Simplifying:

1.7x + 3.4 + 1.7x - 3.4 = 81.6

Combining like terms:

3.4x = 81.6

Dividing both sides by 3.4:

x = 24

So, the speed of each boat in still water is 24 km/h.

Distance Traveled by Each Boat

Now that we know the speed of each boat in still water, we can calculate the distance each boat will travel before they meet.

Distance traveled by the first boat = (x + 2) × 1.7 = (24 + 2) × 1.7 = 43.4 km

Distance traveled by the second boat = (x - 2) × 1.7 = (24 - 2) × 1.7 = 37.4 km

Therefore, the first boat will travel 43.4 km before they meet, and the second boat will travel 37.4 km before they meet.

Distance Traveled by the Boat Traveling with the Current

To find the distance the boat traveling with the current will travel before they meet, we need to subtract the distance traveled by the second boat from the total distance between the ports.

Distance traveled by the boat traveling with the current = Total distance - Distance traveled by the second boat

Distance traveled by the boat traveling with the current = 81.6 km - 37.4 km = 44.2 km

Therefore, the boat traveling with the current will travel 44.2 km before they meet.

Distance Traveled by the Boat Traveling against the Current

To find the distance the boat traveling against the current will travel before they meet, we need to subtract the distance traveled by the first boat from the total distance between the ports.

Distance traveled by the boat traveling against the current = Total distance - Distance traveled by the first boat

Distance traveled by the boat traveling against the current = 81.6 km - 43.4 km = 38.2 km

Therefore, the boat traveling against the current will travel 38.2 km before they meet.

Answer

To summarize: - The boat traveling with the current will travel 44.2 km before they meet. - The boat traveling against the current will travel 38.2 km before they meet.

Please let me know if you need any further assistance!