Primary Divisonal 2012/6
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Please don't post problems (by starting a topic) in the "Primary: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
 Phlembac Adib Hasan
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Primary Divisonal 2012/6
In this diagram, the area of the larger square is three times of the smaller one. The area of the black shaded part is $12$ square unit. Find the area of the bigger square.
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Re: Primary Divisonal 2012/6
Suppose,the area of the larger square is $x^{2}$ and the area of the smaller square is $y^{2}$.
So,$x^{2}=3y^{2}.
x=\sqrt{3}y$
$\frac{1}{2}\times (\sqrt{3}y+y)(\sqrt{3}yy)=12$
Or,$\frac{1}{2}\times (3y^{2}y^{2})=12$
Or,$y^{2}=12$
$\therefore x^{2}=36$
$\therefore$ The area of the bigger square is $36$ square unit
So,$x^{2}=3y^{2}.
x=\sqrt{3}y$
$\frac{1}{2}\times (\sqrt{3}y+y)(\sqrt{3}yy)=12$
Or,$\frac{1}{2}\times (3y^{2}y^{2})=12$
Or,$y^{2}=12$
$\therefore x^{2}=36$
$\therefore$ The area of the bigger square is $36$ square unit
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