Question

За 3 ч лыжник пообещал 51 км,а за следующие 2 ч он пообещал 28 км.На сколько километров в час изменилась его скорость?

Answer 1

51÷3=17
28÷2=14
17-14=3
Его скорость изменилась на 3км

Answer 2

Calculating Change in Speed

To calculate the change in speed, we can first find the initial speed and the final speed, and then find the difference between the two.

Given: - Distance covered in the first 3 hours = 51 km - Distance covered in the next 2 hours = 28 km

Step 1: Calculate Initial Speed The initial speed can be calculated by dividing the distance covered in the first 3 hours by 3.

Initial speed = Distance / Time = 51 km / 3 hours = 17 km/h

Step 2: Calculate Final Speed The final speed can be calculated by dividing the distance covered in the next 2 hours by 2.

Final speed = Distance / Time = 28 km / 2 hours = 14 km/h

Step 3: Calculate Change in Speed The change in speed can be found by subtracting the final speed from the initial speed.

Change in speed = Initial speed - Final speed = 17 km/h - 14 km/h = 3 km/h

Therefore, the skier's speed decreased by 3 km/h.