Question

Велосипедист проехал 20 км со скоростью 10 км/ч и 15 км со скоростью 5. км/ч. Найдите среднюю скорость движения велосипедиста

Answer 1

1) 20:10=2(час) -ехал велос. со скоростью 10км/ч
2) 15:5=3(часа) - ехал со скоростью 15км/ч
3) 2+3=5(часов) - был в пути
4) 20+15=35(км) - проехал за 5 часов
5) 35:5=7(км/ч) - средняя скорость

Answer 2

Calculation of Average Speed

To find the average speed of the cyclist, we can use the formula:

Average Speed = Total Distance / Total Time

In this case, the cyclist traveled a distance of 20 km with a speed of 10 km/h and another distance of 15 km with a speed of 5 km/h.

Let's calculate the total time taken for each distance:

- For the first distance of 20 km with a speed of 10 km/h: - Time = Distance / Speed = 20 km / 10 km/h = 2 hours

- For the second distance of 15 km with a speed of 5 km/h: - Time = Distance / Speed = 15 km / 5 km/h = 3 hours

Now, let's calculate the total distance and total time:

- Total Distance = 20 km + 15 km = 35 km - Total Time = 2 hours + 3 hours = 5 hours

Finally, we can calculate the average speed:

Average Speed = Total Distance / Total Time = 35 km / 5 hours = 7 km/h

Therefore, the average speed of the cyclist is 7 km/h.