MY CART (5)

Use Coupon: CART20 and get 20% off on all online Study Material

ITEM
DETAILS
MRP
DISCOUNT
FINAL PRICE
Total Price: Rs.

There are no items in this cart.
Continue Shopping
Menu
Grade: 10
        
in the adjoining figure the area enclosed between the concentric circles is 770 cm2 if the radius of the outer circle is 21 cm calculate the radius of inner. circle
2 years ago

Answers : (3)

Vasanth SR
askIITians Faculty
1311 Points
							Please enclose the proper supporting document
						
2 years ago
Subhiksha
11 Points
							
Given :
Radius of outer circle = 21cm.
Area between inner & outer circle = 770cm2.
 
Area of outer circle = \prodr2
                                     = 22/7 x 212
                                     = 1386cm2.
 
Area of innercircle = 1386-770
                              = 616cm2.
 
\prodr= 616
      r= 616 x 7/22
      r  =  14cm.
 
Therefore radius of innercircle = 14cm.
2 years ago
amisha
31 Points
							
here we have
the radius of outer circle= 21cm
area between the concentric circle =7702 
\prodR2 = 22/7*21*21
           =1386cm 
\prodr2  =1386cm -770cm
          = 616cm
so,
radius of inner circle 
\prodr2 = 22/7*r2
616 =22/7*r2
616*7/22 = r2
196 = r2
142 = r2
14 = r
hence radius = 14 cm 
one year ago
Think You Can Provide A Better Answer ?
Answer & Earn Cool Goodies


Course Features

  • 731 Video Lectures
  • Revision Notes
  • Previous Year Papers
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Test paper with Video Solution


Course Features

  • 728 Video Lectures
  • Revision Notes
  • Test paper with Video Solution
  • Mind Map
  • Study Planner
  • NCERT Solutions
  • Discussion Forum
  • Previous Year Exam Questions


Ask Experts

Have any Question? Ask Experts

Post Question

 
 
Answer ‘n’ Earn
Attractive Gift
Vouchers
To Win!!! Click Here for details