Question

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

Answer 1

1)V=S:T=51:3=17(км/ч)
2)V=S:T=28:2=14(км/ч)
3)17-14=3(км/ч)-разница

Answer 2

1) 51:3=17 км/ч
2) 28:2=14 км/ч
3) 17-14=3 км/ч
Ответ: на 3 км/ч.

Answer 3

Calculation of Speed Change

To calculate the change in speed, we need to determine the initial speed and the final speed.

Let's break down the information provided:

- In the first 3 hours, the person ran 51 kilometers. - In the next 2 hours, the person ran 28 kilometers.

To find the initial speed, we divide the distance covered in the first 3 hours (51 kilometers) by the time taken (3 hours):

Initial Speed = Distance / Time = 51 km / 3 h = 17 km/h

To find the final speed, we divide the distance covered in the next 2 hours (28 kilometers) by the time taken (2 hours):

Final Speed = Distance / Time = 28 km / 2 h = 14 km/h

Now, to calculate the change in speed, we subtract the final speed from the initial speed:

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

Therefore, the person's speed decreased by 3 kilometers per hour.