find the area of a circular ring formed by circumference of two cocentric circles whose radii are 11 and 4 About the author Everleigh

Answer: 43.98 sq. cm Step-by-step explanation: Let the radii of the outer and inner circles be r 2 and r 1 respectively; we have Area=πr 2 2 −πr 1 2 =π(r 2 2 −r 1 2 ) =π(r 2 −r 1 )(r 2 +r 1 ) =π(5.7−4.3)(5.7+4.3)=π×1.4×10 sq. cm =3.1416×14sq.cm.=43.98 sq. cm Reply

Answer:43.98 sq. cm

Step-by-step explanation:Let the radii of the outer and inner circles be r

2 and r

1

respectively; we have

Area=πr

2

2

−πr

1

2

=π(r

2

2

−r

1

2

)

=π(r

2

−r

1

)(r

2

+r

1

)

=π(5.7−4.3)(5.7+4.3)=π×1.4×10 sq. cm

=3.1416×14sq.cm.=43.98 sq. cm