Question

Поезд шёл 3,5 ч со скоростью 64,4 км/ч. На сколько процентов надо увеличить скорость поезда,чтоб пройти это расстояние за 2 ч 48 мин?

Answer 1

3,5*64,4=225,4 км расстояние
2ч 48мин=2 48/60ч=2,8 ч
225,4:2,8=80,5 км/ч
80,5-64,4=16,1 км/ч на столько увеличилась скорость
16,1*100:64,4=25%
ответ: на 25%

Answer 2

Calculation of the Distance Traveled by the Train

To calculate the distance traveled by the train, we can use the formula:

Distance = Speed × Time

Given that the train traveled for 3.5 hours at a speed of 64.4 km/h, we can calculate the distance as follows:

Distance = 64.4 km/h × 3.5 hours

Let's calculate the distance:

Distance = 225.4 km

Therefore, the train traveled a distance of 225.4 kilometers.

Calculation of the Required Speed Increase

To calculate the required speed increase for the train to cover the same distance in 2 hours and 48 minutes (or 2.8 hours), we can use the formula:

Required Speed = Distance / Time

Given that the distance is 225.4 kilometers and the time is 2.8 hours, we can calculate the required speed as follows:

Required Speed = 225.4 km / 2.8 hours

Let's calculate the required speed:

Required Speed = 80.5 km/h

Therefore, the train would need to increase its speed by approximately 16.1% (rounded to one decimal place) to cover the same distance in 2 hours and 48 minutes.

Please note that the calculations provided are based on the given information and assumptions.