Question

из 2 посёлков расстояние между которыми равно 60 км одновременно выехал велосипедист со скоростью а км/ч и пешеход скорость которого составляет 50% от скорости велосипедиста Какое расстояние будет между ними через 20 минут?​

Answer 1

Ответ:

40 - 0,75 км.

Пошаговое объяснение:

а : 100 * 50 = 0,5а (км/ч) - скорость пешехода, которая составляет 50%

а * 0,5 = 0,5а (км) - проехал за полчаса (0,5 часа) велосипедист

0,5а * 0,5 = 0,25а (км) - прошел пешеход за полчаса

0,5а + 0,25а = 0,75а (км) - расстояние, которое двигаясь навстречу

40 км - расстояние между двумя поселками

40 - 0,75а (км) - расстояние, которое осталось пройти велосипедисту и пешеходу

Answer 2

Calculation of the Distance Between the Cyclist and the Pedestrian

To calculate the distance between the cyclist and the pedestrian after 20 minutes, we need to determine the distances covered by each of them during this time.

Let's assume that the cyclist's speed is a km/h, and the pedestrian's speed is 50% of the cyclist's speed, which is 0.5a km/h.

To find the distance covered by the cyclist in 20 minutes, we need to convert the time to hours. There are 60 minutes in an hour, so 20 minutes is equal to 20/60 = 1/3 hours.

The distance covered by the cyclist in 1/3 hour is given by the formula: distance = speed × time.

Therefore, the distance covered by the cyclist in 20 minutes is (a × 1/3) km.

Similarly, the distance covered by the pedestrian in 20 minutes is (0.5a × 1/3) km.

Now, to find the distance between them after 20 minutes, we subtract the distance covered by the pedestrian from the distance covered by the cyclist:

Distance = (a × 1/3) km - (0.5a × 1/3) km.

Simplifying the expression, we get:

Distance = (2/3)a km - (1/6)a km.

Combining like terms, we have:

Distance = (4/6 - 1/6)a km.

Simplifying further, we get:

Distance = (3/6)a km.

Since the distance between the two villages is 60 km, we can set up the equation:

(3/6)a km = 60 km.

Solving for a, we find:

a = (60 km × 6) / 3 km.

Simplifying, we get:

a = 120 km/h.

Now that we have the value of a, we can substitute it back into the expression for the distance to find the actual distance between the cyclist and the pedestrian after 20 minutes:

Distance = (3/6)(120 km/h) km.

Simplifying, we get:

Distance = 60 km.

Therefore, the distance between the cyclist and the pedestrian after 20 minutes is 60 km.