Question Number 101974 by Ari last updated on 05/Jul/20

Commented byprakash jain last updated on 05/Jul/20

Can you please attach image to this question. There is an option to attach image

Answered by Ari last updated on 05/Jul/20

Commented byprakash jain last updated on 06/Jul/20

Fig A ((πr^2 )/(πR^2 ))=(2/3)⇒(r^2 /R^2 )=(2/3) Fig C: Assume angle α for shaded area (((α/2)R^2 )/(πR^2 ))=(3/5)⇒α=((6π)/5) Fig B (shaded area angle (((α/2)r^2 )/(πR^2 ))=((((6π)/(10))r^2 )/(πR^2 ))=(6/(10))×(2/3)=(2/5)

Commented byAri last updated on 06/Jul/20

Yes,correct!

Answered by JDamian last updated on 06/Jul/20

From fig. C, for any similar circle, the colored part is 3/5. So the colored part in B is 3/5 from the inner circle((3/5)πr^2 ). From A, ((πr^2 )/(πR^2 ))=(2/3) ⇒ πr^2 =(2/3)πR^2 Thus,(((3/5)πr^2 )/(πR^2 ))=(((3/5)∙(2/3)πR^2 )/(πR^2 ))=(3/5)∙(2/3)=(2/5)=40%

Commented byAri last updated on 06/Jul/20

Yes,correct!