Question

.На рисунке изображено круглое озерцо диаметром 200 м. Вокруг него решили обустроить прогулочную дорожку шириной 10 м. Какова будет площадь этой дорожки?

Answer 1

13188кв.м
площадь дорожки= 2х3,14х110х110 - 2х3,14х100х100=75988-62800=13188

Answer 2

Calculation of the Area of the Walkway

To calculate the area of the walkway around the circular lake, we need to subtract the area of the lake itself from the area of the larger circle formed by the outer edge of the walkway.

The diameter of the circular lake is given as 200 meters. This means the radius of the lake is half of the diameter, which is 100 meters.

The width of the walkway is given as 10 meters. This means that the radius of the larger circle formed by the outer edge of the walkway is the sum of the radius of the lake and the width of the walkway, which is 100 meters + 10 meters = 110 meters.

To calculate the area of the walkway, we can subtract the area of the lake from the area of the larger circle.

The formula for the area of a circle is A = πr^2, where A is the area and r is the radius.

Let's calculate the area of the lake first:

Area of the lake = π(100 meters)^2

Now, let's calculate the area of the larger circle formed by the outer edge of the walkway:

Area of the larger circle = π(110 meters)^2

Finally, we can calculate the area of the walkway by subtracting the area of the lake from the area of the larger circle:

Area of the walkway = Area of the larger circle - Area of the lake

Now, let's calculate the area of the walkway using the given values:

Area of the walkway = π(110 meters)^2 - π(100 meters)^2

= π(12100 square meters) - π(10000 square meters)

= π(2100 square meters)

Therefore, the area of the walkway around the circular lake will be 2100 square meters.

Please note that the value of π used in the calculation is an irrational number approximately equal to 3.14159.