Question

Find the diameter of a semicircle whose area is 3925 cm.​

Answer 1

Here the area of the semicircle is given

Area = 3925 cm

We have to find the diameter of the circle

First, we will have to find the radius

area of semicircle = πr²/2

                    3925 = πr²/2

                    7850 = πr²

                    7850 = 3.14 × r²

                  2500 =  r²

                            r = 50 cm

So, diameter = 2 × radius

                     = 2 × 50

                     = 100 cm

Hence, the diameter of the semicircle will be 100 cm

                   

Answer 2

In context to question asked,

We have to determine the value of diameter of semicircle.

From the question,

It is given that,

Area of semicircle $=3925\:cm^2$

As we know that,

Area of semicircle $=\frac{ \Pi r^2}{2}$

As we know that,

Diameter of circle is double to the length of radius.

So, putting the value given in the question in above expression,

We will get,

$3925 =\frac{ \frac{22}{7} \times r^2}{2}\\=>\frac{22}{7} \times r^2 = 3925 \times 2\\=>\frac{22}{7} \times r^2 =7850\\=>r^2 = \frac{7850 \times 7 }{22}\\=>r^2 = \frac{54950}{22}\\=>r = {\sqrt{ \frac{54950}{22}}}\\=>r = 49.977 \approx 50\:cm$

Hence, value of diameter will be $=(2 \times 50) = 100\:cm$