Question

Собственная скорость лодки 9 км/ч , а скорость течения реки 2,5 км/ч. Какой путь прошла лодка за 0,8 ч по течению и 1,6 ч против течения?

Answer 1

0,8*(9+2,5)+1,6*(9-2,5)=0,8*11,5+1,6*6,5=9,2+10,4=19,6км прошла лодка за все время

Answer 2

Calculation of the Boat's Distance Traveled

To calculate the distance traveled by the boat, we need to consider its speed and the direction of the current.

Given: - Boat's speed: 9 km/h - River's current speed: 2.5 km/h - Time traveled downstream (with the current): 0.8 hours - Time traveled upstream (against the current): 1.6 hours

To calculate the distance traveled downstream, we can use the formula: distance = speed x time. Substituting the values, we get: distance downstream = 9 km/h x 0.8 h.

To calculate the distance traveled upstream, we need to consider the effective speed of the boat against the current. The effective speed is the difference between the boat's speed and the current speed. So, the effective speed upstream is: 9 km/h - 2.5 km/h. Using the same formula, we can calculate the distance traveled upstream: distance upstream = (9 km/h - 2.5 km/h) x 1.6 h.

Let's calculate the distances:

- Distance traveled downstream: 9 km/h x 0.8 h = 7.2 km. - Distance traveled upstream: (9 km/h - 2.5 km/h) x 1.6 h = 10.4 km.

Therefore, the boat traveled a distance of 7.2 km downstream and 10.4 km upstream.

Please note that these calculations assume a constant speed and do not take into account other factors such as changes in the current or the boat's speed.