Question

Теплоход шел по озеру 3 часа со скоростью 27 км/ч,а потом 4 часа по реке впадающей в это озеро.Найти весь путь который прошел теплоход за эти 7 часов если скорость течения реки равна 3 км/ч

Answer 1

3*27 = 81 км -  прошел теплоход за 3 часа по реке
т.к. потом он поплыл по реке которая впадает в озеро, значит он плыл против течения. следовательно его скорость уменьшилась на скорость течения
27 - 3 = 24 км/ч  - скорость теплохода по реке
24*4 = 96 км -  проплыл теплоход по реке за 4 часа
81+96 = 177 км - весь путь который прошел теплоход.

Answer 2

Problem Analysis

We are given the following information: - The boat traveled on a lake for 3 hours at a speed of 27 km/h. - The boat then traveled on a river that flows into the lake for 4 hours. - The speed of the river's current is 3 km/h.

We need to find the total distance traveled by the boat in these 7 hours.

Solution

To find the total distance traveled by the boat, we need to calculate the distance traveled on the lake and the distance traveled on the river separately.

# Distance Traveled on the Lake

The distance traveled on the lake can be calculated using the formula:

Distance = Speed × Time

Given that the speed on the lake is 27 km/h and the time spent on the lake is 3 hours, we can calculate the distance traveled on the lake as follows:

Distance on Lake = 27 km/h × 3 hours

# Distance Traveled on the River

To calculate the distance traveled on the river, we need to consider the effect of the river's current. The boat's speed relative to the ground is the difference between its speed in still water and the speed of the current.

Let's denote the speed of the boat in still water as B and the speed of the river's current as C. The speed of the boat relative to the ground is then B - C.

Given that the boat spent 4 hours on the river and the speed of the river's current is 3 km/h, we can calculate the distance traveled on the river as follows:

Distance on River = (B - C) × Time

# Total Distance Traveled

The total distance traveled by the boat is the sum of the distances traveled on the lake and the river.

Total Distance = Distance on Lake + Distance on River

Let's substitute the values we have and calculate the total distance traveled by the boat.

Calculation

Using the given information: - Speed on the lake: 27 km/h - Time on the lake: 3 hours - Time on the river: 4 hours - Speed of the river's current: 3 km/h

We can calculate the total distance traveled by the boat as follows:

Distance on Lake = 27 km/h × 3 hours = 81 km

Distance on River = (B - C) × Time = (B - 3 km/h) × 4 hours

Total Distance = Distance on Lake + Distance on River = 81 km + (B - 3 km/h) × 4 hours

Unfortunately, we don't have the value of the boat's speed in still water (B), so we cannot calculate the exact total distance traveled by the boat.