document.write( "Question 773503: the number of ways in which a man can invite one or more of his 8 friends to dinner \n" ); document.write( "
Algebra.Com's Answer #471605 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
He can have 1 friend for dinner
\n" ); document.write( "He can have 2 friends for dinner
\n" ); document.write( "He can have 3 friends for dinner
\n" ); document.write( "and so on up to
\n" ); document.write( "He can have 8 friends for dinner
\n" ); document.write( "----------------------------
\n" ); document.write( "In each of these 8 cases, use the
\n" ); document.write( "formula for \"+C%288%2Cr%29+\" where \"+r+\" is
\n" ); document.write( "the number of friends invited
\n" ); document.write( "to dinner. Note that you don't use
\n" ); document.write( "permutations since the order of
\n" ); document.write( "the invited friends doesn't matter
\n" ); document.write( "----------------------------
\n" ); document.write( "So, the solution is:
\n" ); document.write( "\"+C%288%2C1%29+%2B+C%288%2C2%29+%2B+C%288%2C3%29+%2B+C%288%2C4%29+\"
\n" ); document.write( "etc. up to \"+C%288%2C8%29+\"
\n" ); document.write( "-----------------
\n" ); document.write( "\"+C%288%2C1%29+=+8%21+%2F+%28+1%21%2A%28+8-1+%29%21+%29+\"
\n" ); document.write( "\"+C%288%2C1%29+=+8%21%2F7%21+\"
\n" ); document.write( "\"+C%288%2C1%29+=+8+\"
\n" ); document.write( "-----------------
\n" ); document.write( "\"+C%288%2C2%29+=+8%21+%2F+%28+2%21%2A%28+8+-+2+%29%21+%29+\"
\n" ); document.write( "\"+C%288%2C2%29+=+8%21+%2F+%28+2%2A1%2A6%2A5%2A4%2A3%2A2%2A1+%29\"
\n" ); document.write( "\"+C%288%2C2%29+=+%28+8%2A7+%29+%2F+2+\"
\n" ); document.write( "\"+C%288%2C2%29+=+28+\"
\n" ); document.write( "---------------
\n" ); document.write( "Continue up to \"+C%288%2C8%29+\" and add up
\n" ); document.write( "all the results.
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