Area of shaded region to unshaded region is

Question

Answer 1

Given AC = 3CD= 2DB
Let CD =r
Then AC=3r ,DB=1.5r, AD=4r, and BC= 2.5r

Now area of the shaded region (S) =1/2×1/4×pi{AD²-CD²+BC²-BD²}

=1/8pi{16r²-r²+6.25r²-2.25r²}=1/8×pi×19r² sq unit

And area of the unshaded region (U) =1/2×1/4pi{AC²+CD²+BD²}

=1/8pi{16r²+r²+2.25r²}=1/8pi 19.25r² sq unit

so required ratio, S/U = 19:19.25 =76:77