document.write( "Question 1096519: If you rotate a sheet of paper by 180 degrees, digits 0, 1, and 8 do not change; 6 becomes a 9; 9 becomes a 6; while other digits lose their meaning. Count all the 7-digit numbers that do not change upon rotation by 180 degrees. \n" ); document.write( "
Algebra.Com's Answer #711719 by Gentle Phill(18)![]() ![]() You can put this solution on YOUR website! #SOLN \n" ); document.write( ". \n" ); document.write( "...Let's crack some nuts... \n" ); document.write( ". \n" ); document.write( "Collect data.. \n" ); document.write( ". \n" ); document.write( "Only numbers with 0, 1 and 8 do not oppose the motion. \n" ); document.write( ". \n" ); document.write( "Process data.. \n" ); document.write( ". \n" ); document.write( "Form seven-digit numbers with 0, 1 and 8 \n" ); document.write( ". \n" ); document.write( "Millions place can take only 2 digits (1 and 8) \n" ); document.write( ". \n" ); document.write( "Others (from hundreds of thousand down to unit) can take all 3 each. \n" ); document.write( ". \n" ); document.write( "We have: \n" ); document.write( ". \n" ); document.write( "[2][3][3][3][3][3][3] nos \n" ); document.write( ". \n" ); document.write( "Give out Information.. \n" ); document.write( ". \n" ); document.write( "558 seven-digit numbers can be rotated half way but remain same. \n" ); document.write( ". \n" ); document.write( "#CRACKED \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( ". \n" ); document.write( "Your friend, \n" ); document.write( "Francis. \n" ); document.write( " |