Question

the area of two equal circles in the figure is 308 cm square. Find the perimeter of the rectangle

With solution!!!
$\pi{r}^{2}$
​

Answer 1

Answer:

Perimeter of rectangle is 84 cm.

Step-by-step explanation:

Given:

Area of two equal circles =308 Sq.cm.

∴ Area of 1 circle = 308 /2 =154 sq.cm.

As we know;

Area of circle = $\pi r^{2}$           ( where r=radius of the circle)

            154 = (22/7) $r^{2}$       ( $\pi$ =22/7)

             $r^{2}$  = (154 × 7)/22

             r = $\sqrt{49}$  =7 cm.

∴ Diameter of 1 circle = 2r = 2 × 7= 14 cm.

∴ Diameter of both the circles = 2 × 14 = 28 cm.

Length of rectangle = diameter of both circle= 28 cm.

Breadth of rectangle = diameter of 1 circle = 14 cm.

∴ Perimeter of rectangle = 2 ( length + breadth )

                                        = 2 ( 28 + 14)

                                        = 2 ×42 = 84 cm.

Answer 2

Answer:

Perimeter of the rectangle = 84 cm

Step-by-step explanation:

According to given figure

diameter of circle 1 = diameter of circle 2

Length of the rectangle = diameter of circle 1 + diameter of circle 2

Breadth of the rectangle = diameter of any one circle

Now, it is given that area of two equal circle = 308 cm²

Area of circle = πr² where r = radius of the circle

According to question,

πr² + πr² = 308

2πr² = 308

πr² = 308/2 = 154

(22/7)r² = 154     (π = 22/7)

r² = 154 × 7 / 22

r² = 49

r = 7 cm

diameter = 2r = 2×7 = 14

Length of the rectangle = 14 + 14 = 28 cm

Breadth of the rectangle = 14 cm

Perimeter of the rectangle = 2(length+breadth)

= 2(28+14) = 2 × 42 = 84 cm

∴ Perimeter of the rectangle = 84 cm