document.write( "Question 1171116: Hi\r
\n" ); document.write( "\n" ); document.write( "Andrew was given a rectangular cardboard 28cm by 16cm. How many right angle triangles 4cm high base 3cm could cut out. \r
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Algebra.Com's Answer #796015 by ikleyn(52782)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "Andrew was given a rectangular cardboard 28cm by 16cm. How many right angle triangles 4cm high base 3cm could cut out.
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document.write( "Two right angled triangles with the legs of 3 cm and 4 cm, placed hypotenuse to hypotenuse, form a 3x4-rectangle.\r\n" );
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document.write( "Let's calculate how many such rectangles can be placed onto the 28x16 cm cardboard.\r\n" );
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document.write( "We have two basic placements.\r\n" );
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document.write( "One placement is to direct the 4-cm side of the rectangle along its 28 cm dimension.\r\n" );
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document.write( "By doing this way, we have 28/4 = 7 rectanles in this direction and, OBVIOSLY, 5 rectangles in the perpendicular direction,\r\n" );
document.write( "                                                     (because 16/3 = 5.33 = 5 when rounded to the closest smaller integer).\r\n" );
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document.write( "In all, we have 7*5 = 35 rectangles and, hence, 35*2 = 70 right angled triangles at such placement.\r\n" );
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document.write( "Next, consider another placement, directing the 4-cm side side along the 16-cm side of the cardboard.\r\n" );
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document.write( "We have then the 3-cm side along the 28-cm side of the cardboard.\r\n" );
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document.write( "By doing this way, we have 4 rectangles along the 16-cm side of the cardboard and, OBVIOUSLY, 9 rectangles along its 28 cm side \r\n" );
document.write( "                                                               (because 28/3 = 9.33 = 9 rounded to the closest smaller integer).\r\n" );
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document.write( "In all, we have 4*9 = 36 rectangles and, hence, 36*2 = 72 right angled triangles at such placement.\r\n" );
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document.write( "Of these two opportunities, we chose the placement, which gives maximum numer of rectangles (36) and maximum number of triangles (72).\r\n" );
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document.write( "ANSWER.  Maximum number of triangles is 72.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Such problems teachers give to young  (advanced ?)  students of  5th - 6th  grades to check if they are able
\n" ); document.write( "to think on self-standing basis and to teach them to solve such problems accurately  (and to think accurately)
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\n" ); document.write( "\n" ); document.write( "The solution by  @MathLover1,  based on consideration the areas  ONLY,  gives an  ESTIMATION  ONLY
\n" ); document.write( "for the maximum number of triangles from the top,  but does not give the exact number of triangles.\r
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\n" ); document.write( "\n" ); document.write( "The solution by  @MathLover1  IS  NOT  what is expected.\r
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\n" ); document.write( "\n" ); document.write( "Learn on how to solve such problems  (and how to teach your students,  if you are a teacher) - from my post.\r
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