Question

The areas of two concentric circles are 1386 cm square and 1886.5 cm.square respectively. Find the width of the ring

Answer 1

Solution:

Given: The areas of two concentric circles are 1386 sq.cm and 1886.5 sq.cm. respectively.

Width of the ring = larger radius - smaller radius (of the concentric circle)
                           w=R-r
                    
 Area of larger circle=πR²
                     1886.5=22/7(R²)
         1886.5 x 7/22=R²
           85.75x7=R²
             600.25=R²
                      R=√600.25
                      R=24.5cm

Area of smaller circle=πr²
                            1386=22/7(r²)
                1386 x 7/22=r²
                         63 x 7=r²
                                 r²=441
                                 r=√441
                                 r=21cm
Width of the ring(formed by concentric circles)=R-r
                                                                                =24.5-21
                                                                                =3cm
∴Width of the ring = 3cm

Answer 2

Answer:

in the pic

Step-by-step explanation:

firstly find the radius with two areas and then subtract the radious to find width