Question

Длина парка прямоугольной формы на 400 метров больше,чем ширина,причём отношение длины и ширины равно отношению 5:3.Сколько времени потребуется пешеходу,чтобы обойти парк по периметру,если его скорость 5км/ч?

Answer 1

составим уравнение где х-ширина парка, тогда х+400 длинна парка

 

(х+400)/х = 5/3  приводим к общему знаменателю 3х

(х+400)*3=5х

3х+1200=5х

5х-3х=1200

2х=1200

х=600 ширина парка

400+600= 1000 м длинна парка

Р парка=1600*2=3200 м периметр

3200 м=3,2 км

 

3,2/5=0,64 часа, или 60*0,64=38,4 мин

 

можно еще 60 мин / 5 км = 12 мин (за 12 мин 1 км)

12*3,2=38,4 мин

 

 

 

Answer 2

Calculation of the Park's Dimensions

To find the dimensions of the rectangular park, we are given that the length is 400 meters longer than the width, and the ratio of the length to the width is 5:3.

Let's assume the width of the park is x meters. According to the given information, the length of the park is x + 400 meters.

Using the ratio of the length to the width, we can set up the following equation:

Length / Width = 5 / 3

Substituting the values, we get:

(x + 400) / x = 5 / 3

To solve for x, we can cross-multiply:

3(x + 400) = 5x

Expanding and simplifying the equation:

3x + 1200 = 5x

1200 = 5x - 3x

1200 = 2x

Dividing both sides by 2:

x = 600

Therefore, the width of the park is 600 meters, and the length is 600 + 400 = 1000 meters.

Calculation of the Perimeter

To calculate the time it takes for a pedestrian to walk around the park, we need to find the perimeter of the rectangular park.

The perimeter of a rectangle is given by the formula:

Perimeter = 2 * (Length + Width)

Substituting the values we found earlier:

Perimeter = 2 * (1000 + 600)

Perimeter = 2 * 1600

Perimeter = 3200 meters

Calculation of the Time Required

Given that the pedestrian's speed is 5 km/h, we can convert the perimeter from meters to kilometers:

Perimeter = 3200 meters = 3.2 kilometers

To calculate the time required, we can use the formula:

Time = Distance / Speed

Substituting the values:

Time = 3.2 km / 5 km/h

Time = 0.64 hours

Since the pedestrian's speed is given in kilometers per hour, we can convert the time to minutes by multiplying by 60:

Time = 0.64 hours * 60 minutes/hour

Time = 38.4 minutes

Therefore, it would take the pedestrian approximately 38.4 minutes to walk around the park.

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