Difference between revisions of "1971 AHSME Problems/Problem 28"

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== Solution ==
 
== Solution ==
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<asy>
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import geometry;
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point B = origin;
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point A = (3,5);
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point C = (7,0);
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triangle t = triangle(A,B,C);
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point D = B*9/10 + A/10;
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point E;
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// Defining point E
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pair[] e = intersectionpoints(parallel(D,line(B,C)),A--C);
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E = e[0];
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// Triangle ABC and Parallel Segment
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draw(t);
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draw(D--E);
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// Point Labels
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dot(A);
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label("A",A,NW);
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dot(B);
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label("B",B,SW);
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dot(C);
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label("C",C,SE);
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dot(D);
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label("D",D,NW);
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dot(E);
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label("E",E,NE);
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</asy>
  
 
<math>\boxed{\textbf{(C) }200}</math>.
 
<math>\boxed{\textbf{(C) }200}</math>.

Revision as of 11:51, 7 August 2024

Problem

Nine lines parallel to the base of a triangle divide the other sides each into $10$ equal segments and the area into $10$ distinct parts. If the area of the largest of these parts is $38$, then the area of the original triangle is

$\textbf{(A) }180\qquad \textbf{(B) }190\qquad \textbf{(C) }200\qquad \textbf{(D) }210\qquad  \textbf{(E) }240$

Solution

[asy]  import geometry;  point B = origin; point A = (3,5); point C = (7,0); triangle t = triangle(A,B,C);  point D = B*9/10 + A/10; point E;  // Defining point E pair[] e = intersectionpoints(parallel(D,line(B,C)),A--C); E = e[0];  // Triangle ABC and Parallel Segment draw(t); draw(D--E);  // Point Labels dot(A); label("A",A,NW); dot(B); label("B",B,SW); dot(C); label("C",C,SE); dot(D); label("D",D,NW); dot(E); label("E",E,NE);  [/asy]

$\boxed{\textbf{(C) }200}$.

See Also

1971 AHSC (ProblemsAnswer KeyResources)
Preceded by
Problem 27
Followed by
Problem 29
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
All AHSME Problems and Solutions

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