Question

Катер проплыл 84 км за 3 часа, после чего ему осталось проплыть ещё 140 км. За сколько времени он проплывёт оставшееся расстояние,если увеличит скорость на 7 км/ч?

Answer 1

84:3=28
осталось 140 км
28+7=35
140:35= 4 часа

Answer 2

Problem Analysis

We are given that a boat traveled 84 km in 3 hours and then needs to travel an additional 140 km. The boat will increase its speed by 7 km/h. We need to determine how long it will take for the boat to cover the remaining distance.

Solution

To find the time it will take for the boat to cover the remaining distance, we can use the formula:

Time = Distance / Speed

Let's calculate the time it will take for the boat to cover the remaining distance.

Calculation

The boat traveled 84 km in 3 hours, so its initial speed was:

Speed = Distance / Time = 84 km / 3 hours = 28 km/h.

The boat needs to cover an additional 140 km. If its speed increases by 7 km/h, its new speed will be:

New Speed = Initial Speed + Increase in Speed = 28 km/h + 7 km/h = 35 km/h.

Using the formula for time, we can calculate the time it will take for the boat to cover the remaining distance:

Time = Distance / Speed = 140 km / 35 km/h = 4 hours.

Therefore, it will take the boat 4 hours to cover the remaining distance of 140 km.

Answer

The boat will take 4 hours to cover the remaining distance of 140 km if its speed is increased by 7 km/h.

Note: The sources provided did not directly answer the question, but the calculations were based on the given information and general formulas for time, distance, and speed.