document.write( "Question 488902: 1. If n(A) = 8, then how many proper subsets does A have?\r
\n" ); document.write( "\n" ); document.write( "2. At a local college, a survey was taken to determine where students studied on campus. Of 180 students surveyed, it was determined that:\r
\n" ); document.write( "\n" ); document.write( "89 studied in the library
\n" ); document.write( "76 studied in the student center
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\n" ); document.write( "\n" ); document.write( " Of those interviewed,\r
\n" ); document.write( "\n" ); document.write( "a. how many studied in only the library?\r
\n" ); document.write( "\n" ); document.write( "b. how many studied in only the student center?\r
\n" ); document.write( "\n" ); document.write( "c. how many did not study in either location?\r
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Algebra.Com's Answer #852352 by ikleyn(52858)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "1. If n(A) = 8, then how many proper subsets does A have?
\n" ); document.write( "2. At a local college, a survey was taken to determine where students studied on campus. Of 180 students surveyed, it was determined that:
\n" ); document.write( "89 studied in the library
\n" ); document.write( "76 studied in the student center
\n" ); document.write( "55 studied in both places
\n" ); document.write( "Of those interviewed,
\n" ); document.write( "a. how many studied in only the library?
\n" ); document.write( "b. how many studied in only the student center?
\n" ); document.write( "c. how many did not study in either location?
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\n" ); document.write( "\n" ); document.write( "        For part  (1),  tutor  @Theo wrote a long essay,  but his solution is  TOTALLY  WRONG.\r
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\n" ); document.write( "\n" ); document.write( "        I came to bring a correct solution to part  (1).\r
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document.write( "It is well known fact that every finite set of 'n' elements has precisely  \"2%5En\" subsets,\r\n" );
document.write( "including the empty set and the set itself as a subset.\r\n" );
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document.write( "In our problem, n = 8,  so there are  \"2%5E8\" = 256 subsets, as described.\r\n" );
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document.write( "From these 256 subsets, we should exclude one subset, which is the set itself, to get proper subsets.\r\n" );
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document.write( "So, in this problem, there are  \"2%5E8\" - 1 = 256 - 1 = 255 proper subsets.\r\n" );
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document.write( "ANSWER.  Set A has 255 proper subsets.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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