Question

Choose all that compute the correct area of the circle. The area of a circle with a diameter of 5 cm. A ≈ 19.63 cm2 The area of a circle with a radius of 3 cm. A ≈ 28.27 cm2 The area of a circle with a diameter of 4 cm. A ≈ 50.27 cm2 The area of a circle with a radius of 7 cm. A ≈ 153.94 cm2

Answer 1

19.63cm^2

28.16cm^2

153.86cm^2

Answer 2

Area of a circle with radius "r" can be found using the formula :

`Area = \pi r^(2)`

Also we have radius = diameter / 2

So let us find area of all the given diameter or radius.

(1)

we are given diameter =5cm

So first finding radius, radius = diameter/2 =5/2 =2.5

Now plugging this value of radius in the formula for area we have,

`Area = \pi (2.5)^(2)`

`Area = 3.14 * 6.25`

Area =19.625 cm² or Area =19.63 cm²

So first answer is correct

(2)

radius =3cm

Plugging this value in the formula for area ,

`Area = \pi r^(2)`

`Area = 3.14* (3)^(2)`

`Area = 3.14*9`

Area =28.26cm²

(3)

Diameter =4cm

Radius = 4/2 =2 cm

`Area = \pi r^(2)`

`Area = 3.14* 2^(2)`

Area =12.56 cm²

(4)

Radius =7cm

`Area = \pi r^(2)`

`Area = 3.14 * 7^(2)`

`Area = 3.14 * 49`

Area =153.86 cm²