document.write( "Question 44848: I am a whole number between 40,000 and 50,000. When I am divided by 2, the asnwer is a perfect square. When I am divided by 3, the answer is a perfect cube. Who am I?\r
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document.write( "I need to explain how I got this\r
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document.write( "Help \n" );
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Algebra.Com's Answer #29722 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! I am a whole number between 40,000 and 50,000. When I am divided by 2, the asnwer is a perfect square. When I am divided by 3, the answer is a perfect cube. Who am I? \n" ); document.write( "I need to explain how I got this \n" ); document.write( "------------------------------------------------------ \n" ); document.write( "Let the number be #; then 40000<#<50000 \n" ); document.write( "When # is divided by 3 the result is a perfect cube, as follows: \n" ); document.write( "#/3=y^3 \n" ); document.write( "Then #=3y^3 \n" ); document.write( "Put that into the inequality, as follows: \n" ); document.write( "40000<3y^3<50000 \n" ); document.write( "Divide thru by 3 to get \n" ); document.write( "13333.333< y^3 <16666.666...\r \n" ); document.write( "\n" ); document.write( "Take the cube root from left to right to get: \n" ); document.write( "23.7126...< y <25.5436...\r \n" ); document.write( "\n" ); document.write( "Therefore y is either 24 or 25\r \n" ); document.write( "\n" ); document.write( "Then #=3*24^3 or #=3*25^3\r \n" ); document.write( "\n" ); document.write( "If #=3^24^3=41472 \n" ); document.write( "When we divide this by 2 we get 20736 \n" ); document.write( "If we take the square root we get 144. \n" ); document.write( "So when 41472 is divided by 2 we DO get a perfect square. \n" ); document.write( "And when we divide 41472 by 3 we DO get a perfect cube.\r \n" ); document.write( "\n" ); document.write( "Could #=3*25^3 also be an acceptable answer? \n" ); document.write( "#=3*25^3= 46875 \n" ); document.write( "When we divide by 2 we get 23437.5 \n" ); document.write( "which is not a perfect square.\r \n" ); document.write( "\n" ); document.write( "So the number you are looking for is 41472.\r \n" ); document.write( "\n" ); document.write( "Cheers, \n" ); document.write( "Stan H.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |