Question

The radius of a circle is 20 cm . It is divided into 4 parts of equal area by drawing three concentric circles inside it. Then the radius of the largest of three concentric circles drawn is

Answer 1

Answer:

10root3

Step-by-step explanation:

Total Area=pi × r^2

therefore here area = pi × 400

now three circles are drawn inside dividing the circle into 4 equal areas.

Therfore area of each Circle =(Pi×400)/4

=pi × 100

therfore the largest concentric circle which is the third one will have a area of pi × 300...

on comparing with pi ×r^2

pi * r^2= pi*300

r^2=300

$10 \sqrt{3}$