Question

find perimeter of semi-circle of radius 35 cm including its diameter​

Answer 1

perimeter of semi circle= πr+2r

= r(π+2)

=55+35=90cm

Answer 2

Answer:

Perimeter of a semi-circle is $109.9$ cm.          

 Diameter of the semi-circle is $70$ cm.

Step-by-step explanation:

Given : Radius of a circle = $35$ cm

To find : i) The perimeter of semi-circle

           ii) Diameter of the semi-circle

Solution :

• It is given that the radius of a circle = $35$ cm
• We have to find i) The perimeter of semi-circle

                       ii) Diameter of the semi-circle

• Perimeter is the outer boundary of a circle.
• The formula for perimeter of semi-circle is given by,

        Perimeter of a semi-circle = $\frac{2\pi r}{2}$

                                               = $\frac{2*3.14*35}{2}$

                                               = $109.9$ cm

• Diameter of a circle is twice the radius.

• So,

    Diameter of the semi-circle = $2r$

                                             = $2*35$

                                             = $70$ cm

• ∴ Perimeter of a semi-circle is $109.9$ cm.          
•  Diameter of the semi-circle is $70$ cm.