Difference between revisions of "2013 AMC 8 Problems/Problem 24"

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(=Video Solution for Problems 21-25)
 
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==Problem==
 
==Problem==
 +
Squares <math>ABCD</math>, <math>EFGH</math>, and <math>GHIJ</math> are equal in area. Points <math>C</math> and <math>D</math> are the midpoints of sides <math>IH</math> and <math>HE</math>, respectively. What is the ratio of the area of the shaded pentagon <math>AJICB</math> to the sum of the areas of the three squares?
  
==Solution==
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<math> \textbf{(A)}\hspace{.05in}\frac{1}{4}\qquad\textbf{(B)}\hspace{.05in}\frac{7}{24}\qquad\textbf{(C)}\hspace{.05in}\frac{1}{3}\qquad\textbf{(D)}\hspace{.05in}\frac{3}{8}\qquad\textbf{(E)}\hspace{.05in}\frac{5}{12}</math>
  
==See Also==
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<asy>
{{AMC8 box|year=2013|num-b=23|num-a=25}}
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pair A,B,C,D,E,F,G,H,I,J;
{{MAA Notice}}
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 +
A = (0.5,2);
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B = (1.5,2);
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C = (1.5,1);
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D = (0.5,1);
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E = (0,1);
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F = (0,0);
 +
G = (1,0);
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H = (1,1);
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I = (2,1);
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J = (2,0);
 +
draw(A--B);
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draw(C--B);
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draw(D--A); 
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draw(F--E);
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draw(I--J);
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draw(J--F);
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draw(G--H);
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draw(A--J);
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filldraw(A--B--C--I--J--cycle,grey);
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draw(E--I);
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dot("$A$", A, NW);
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dot("$B$", B, NE);
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dot("$C$", C, NE);
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dot("$D$", D, NW);
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dot("$E$", E, NW);
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dot("$F$", F, SW);
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dot("$G$", G, S);
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dot("$H$", H, N);
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dot("$I$", I, NE);
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dot("$J$", J, SE);
 +
</asy>

Latest revision as of 09:59, 16 July 2024

Problem

Squares $ABCD$, $EFGH$, and $GHIJ$ are equal in area. Points $C$ and $D$ are the midpoints of sides $IH$ and $HE$, respectively. What is the ratio of the area of the shaded pentagon $AJICB$ to the sum of the areas of the three squares?

$\textbf{(A)}\hspace{.05in}\frac{1}{4}\qquad\textbf{(B)}\hspace{.05in}\frac{7}{24}\qquad\textbf{(C)}\hspace{.05in}\frac{1}{3}\qquad\textbf{(D)}\hspace{.05in}\frac{3}{8}\qquad\textbf{(E)}\hspace{.05in}\frac{5}{12}$

[asy] pair A,B,C,D,E,F,G,H,I,J;  A = (0.5,2); B = (1.5,2); C = (1.5,1); D = (0.5,1); E = (0,1); F = (0,0); G = (1,0); H = (1,1); I = (2,1); J = (2,0);  draw(A--B);  draw(C--B);  draw(D--A);   draw(F--E);  draw(I--J);  draw(J--F);  draw(G--H);  draw(A--J);  filldraw(A--B--C--I--J--cycle,grey); draw(E--I); dot("$A$", A, NW); dot("$B$", B, NE); dot("$C$", C, NE); dot("$D$", D, NW); dot("$E$", E, NW); dot("$F$", F, SW); dot("$G$", G, S); dot("$H$", H, N); dot("$I$", I, NE); dot("$J$", J, SE); [/asy]