Question

конькобежец бежал дистанцию со скоростью 2/5, и за 200 метров до финиша увеличил скорость на 1/10. За сколько секунд конькобежец пробежал эти 200 метров?.

Answer 1

Calculation of the Time Taken by the Skater

To calculate the time taken by the skater to cover the distance of 200 meters, we need to consider the initial speed and the increased speed.

Let's break down the problem step by step:

1. The skater initially runs at a speed of 2/5. 2. When the skater is 200 meters away from the finish line, the skater increases their speed by 1/10.

To find the time taken, we can use the formula:

Time = Distance / Speed

Let's calculate the time taken by the skater.

1. Initial speed = 2/5 2. Distance = 200 meters

Using the formula, we can calculate the time taken to cover the distance of 200 meters at the initial speed:

Time1 = Distance / Speed1

Time1 = 200 / (2/5)

Simplifying the expression:

Time1 = 200 * (5/2)

Time1 = 1000 / 2

Time1 = 500 seconds

Now, let's calculate the time taken to cover the remaining 200 meters at the increased speed.

1. Increased speed = Initial speed + 1/10 2. Distance = 200 meters

Using the formula, we can calculate the time taken to cover the distance of 200 meters at the increased speed:

Time2 = Distance / Speed2

Time2 = 200 / (2/5 + 1/10)

Simplifying the expression:

Time2 = 200 / (4/10 + 1/10)

Time2 = 200 / (5/10)

Time2 = 200 * (10/5)

Time2 = 400 seconds

To find the total time taken, we add the time taken at the initial speed (Time1) and the time taken at the increased speed (Time2):

Total Time = Time1 + Time2

Total Time = 500 + 400

Total Time = 900 seconds

Therefore, the skater took 900 seconds to cover the distance of 200 meters.

Please note that the above calculation assumes a constant speed throughout the distance. If there are any other factors involved, such as acceleration or deceleration, the calculation may differ.