CBSE Class 10CBSE
Share
Notifications

View all notifications

The Area Enclosed Between the Concentric Circles is 770cm2. If the Radius of Outer Circle 21cm. Find the Radius of Inner Circle - CBSE Class 10 - Mathematics

Login
Create free account


      Forgot password?

Question

The area enclosed between the concentric circles is 770cm2. If the radius of outer circle 21cm. find the radius of inner circle

Solution

Radius of outer circle = 21𝑐𝑚

Radius of inner circle = 𝑅2

Area between concentric circles = area of outer circle – area of inner circle

⇒ 770 =`22/7`(212 − R22)

⇒ 212 − 𝑅22 = 35 × 7 = 245

⇒ 441 – 245 = 𝑅22

⇒𝑅2= `sqrt(196)` = 14 𝑐𝑚

Radius of inner circle = 14cm.

  Is there an error in this question or solution?

APPEARS IN

Solution The Area Enclosed Between the Concentric Circles is 770cm2. If the Radius of Outer Circle 21cm. Find the Radius of Inner Circle Concept: Areas of Combinations of Plane Figures.
S
View in app×