document.write( "Question 112572: I'm not quite sure what this means...\r
\n" ); document.write( "\n" ); document.write( "Find the sum of the infinite geometric series:
\n" ); document.write( ".8+.08+.008\r
\n" ); document.write( "\n" ); document.write( "PLEASE help! thanks <3
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Algebra.Com's Answer #82093 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
This infinite series is just another way of saying
\n" ); document.write( "\".88888888888\"... on and on forever and ever. In the
\n" ); document.write( "problem, they just pulled out each \"8\", so they got
\n" ); document.write( "\".8+%2B+.08+%2B+.008+%2B+.0008\"... on and on forever
\n" ); document.write( "Believe it or not, \".88888888888\"... =\"8%2F9\"
\n" ); document.write( "You find it with a little trick.
\n" ); document.write( "First call the repeating decimal \"n\".
\n" ); document.write( "Then show what \"10n\" is
\n" ); document.write( "\"10n+=+8.88888888\"...
\n" ); document.write( "\"n+=+.888888888\"...
\n" ); document.write( "subtract \"n\" from \"10n\". Everything to the right of the
\n" ); document.write( "decimal points cancel out. I'm left with
\n" ); document.write( "\"9n+=+8\"
\n" ); document.write( "\"n+=+8%2F9\"answer
\n" ); document.write( "OK, what if you had \".137137137137137\"... on and on and on?
\n" ); document.write( "What's the value? Use the same trick a little differently
\n" ); document.write( "\"1000n+=+137.137137137137\"...
\n" ); document.write( "\"n+=+.137137137137137\"...
\n" ); document.write( "now subtract
\n" ); document.write( "\"999n+=+137\"
\n" ); document.write( "\"n+=+137%2F999\"answer
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