Question

Катер в первый час плыл со скоростью 18км/ч. Во второй час уменьшил скорость на 15% а в третий час увеличел на 20%. какова скорость катера в третий час?

Answer 1

Найдем уменьшенную скорость
18-(0,15*18)=18-2,7=15,3 км/ч
найдем увеличенную скорость
15,3+(0,2*15,3)=15,3+3,06=18,36 км/ч

Answer 2

Calculating the Boat's Speed in the Third Hour

To calculate the boat's speed in the third hour, we'll follow these steps:

1. Initial Speed: The boat's initial speed was 18 km/h. 2. Speed Reduction in the Second Hour: The boat reduced its speed by 15% in the second hour. 3. Speed Increase in the Third Hour: The boat then increased its speed by 20% in the third hour.

Calculation Steps

1. Initial Speed: 18 km/h. 2. Speed Reduction in the Second Hour: 15% of 18 km/h is 2.7 km/h. So, the speed was reduced to 18 km/h - 2.7 km/h = 15.3 km/h. 3. Speed Increase in the Third Hour: 20% of 15.3 km/h is 3.06 km/h. So, the speed increased to 15.3 km/h + 3.06 km/h = 18.36 km/h.

Therefore, the boat's speed in the third hour was 18.36 km/h.