Question

Найдите площадь 5/7 круга, радиус которого 2/10. Число П округлите до десятых. Найдите площадь круга, если 4/9 длины окружности этого круга 46/10 см. Число П округлите. Помогите пож. решить.

Answer 1

В первом случае получится 31/50  во втором случае получится 8 целых 4449/4800

Answer 2

Calculation of the Area of a Circle with a Radius of 2/10

To find the area of a circle, we can use the formula A = πr^2, where A represents the area and r represents the radius of the circle.

Given that the radius of the circle is 2/10, we can substitute this value into the formula:

A = π(2/10)^2

To calculate the area, we need to determine the value of π. From the search results, we find that π is approximately equal to 3.14.

Substituting the values into the formula, we get:

A = 3.14 * (2/10)^2

Simplifying the expression, we have:

A = 3.14 * (4/100)

Multiplying the numbers, we get:

A = 12.56/100

To round the result to the nearest tenth, we can divide the numerator by 10:

A ≈ 1.26

Therefore, the area of the circle with a radius of 2/10 is approximately 1.26 square units.

Calculation of the Area of a Circle with a Given Circumference

To find the area of a circle when the length of its circumference is given, we can use the formula A = (C^2) / (4π), where A represents the area and C represents the circumference of the circle.

Given that the length of the circumference is 46/10 cm, we can substitute this value into the formula:

A = (46/10)^2 / (4π)

To calculate the area, we need to determine the value of π. From the search results, we find that π is approximately equal to 3.14.

Substituting the values into the formula, we get:

A = (46/10)^2 / (4 * 3.14)

Simplifying the expression, we have:

A = (46/10)^2 / 12.56

To calculate the area, we need to square the numerator:

A = (2116/100) / 12.56

Dividing the numbers, we get:

A ≈ 16.85 / 12.56

A ≈ 1.34

Therefore, the area of the circle with a circumference of 46/10 cm is approximately 1.34 square units.

Please let me know if there is anything else I can help you with!