document.write( "Question 847786: There are 24 students in a class. Each student is wearing either a hat or gym shoes or both.
\n" ); document.write( "16 are wearing hats
\n" ); document.write( "20 are wearing shoes
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Algebra.Com's Answer #512076 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "There are 24 students in a class. Each student is wearing either a hat or gym shoes or both.\r\n" );
document.write( "16 are wearing hats\r\n" );
document.write( "20 are wearing shoes\r\n" );
document.write( "How many are wearing both?\r\n" );
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document.write( "Use the formula:  N(A or B) = N(A) + N(B) - N(A and B)\r\n" );
document.write( "Where N() means the number of \r\n" );
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document.write( "A is the event of wearing a hat.\r\n" );
document.write( "B is the event of wearing gym shoes.\r\n" );
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document.write( " N(A or B) = N(A) + N(B) - N(A and B)\r\n" );
document.write( "        24 =  16  +  20  - N(A and B)\r\n" );
document.write( "        24 =  36 - N(A and B)\r\n" );
document.write( "N(A and B) = 12\r\n" );
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document.write( "Edwin
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