The radius of a circle is 20 cm. It is divided into four parts of equal area by drawing three concentric circles inside it. Then, the radius of the largest of three concentric circles drawn is: (Take a = 3.14)
Answers
Answered by
1
Answer:
Step-by-step explanation:
Given :
Radius of a circle, OB (R) = 20 cm
Let Radius of three concentric circles ,OA (r)= x cm.
Area of the 4th region = ¼ × Area the given circle
π(OB² - OA²) = ¼ × πR²
[Area of circular ring = π(R² - r²)]
(20² - x²) = ¼ × R²
400 - x² = ¼ × 20²
400 - x² = ¼ × 400
400 - x² = 100
400 - 100 = x²
x² = 300
x = √300
x = √100 × 3
x = 10√3
Radius of the largest of three concentric circle = 10√3 cm
Hence, the radius of the largest of three concentric circle is 10√3 cm.
HOPE THIS ANSWER WILL HELP YOU….
Step-by-step explanation:
Similar questions