document.write( "Question 1188811: a school with 60 teachers is on alert during a nighttime
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\n" ); document.write( "to inform teachers whether the school will open the next day , the princeipal will call four teachers
\n" ); document.write( "each of whom will then call 2 others
\n" ); document.write( "and each of these will again call 2 others
\n" ); document.write( "so on untill all 60 have been contacted
\n" ); document.write( "how many people have to make 2 calls? \n" ); document.write( "

Algebra.Com's Answer #819990 by ikleyn(52788) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " To solve the problem, I prepared this Table below\r
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document.write( "       T            A            B            L            E\r\n" );
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document.write( "    step                             how many           how mamy \r\n" );
document.write( "     #                             teachers know    teachers don't know\r\n" );
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document.write( "     1        a principal               4              60 - 4 = 56\r\n" );
document.write( "            calls to 4 teachers\r\n" );
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document.write( "     2        4 teachers call\r\n" );
document.write( "            to 8 other teachers      4 +  8 = 12       56 - 8 = 48 \r\n" );
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document.write( "     3        8 teachers calls\r\n" );
document.write( "            to 16 other teachers    12 + 16 = 28       48 - 16 = 32 \r\n" );
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document.write( "     4       16 teacher calls\r\n" );
document.write( "            to 32 other teachers    28 + 32 = 60       32 - 32 =  0 \r\n" );
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document.write( "Now from the table, the number of people (= of teachers) who made 2 calls is  4 + 8 + 16 = 28.\r\n" );
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document.write( "ANSWER.  The number of people who made 2 calls is  28.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Now, as you see this solution and this table, you can, probably, organize \r
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