document.write( "Question 1082552: How many numbers between 1 and 100 (inclusive) are divisible by 5 or 8?\r
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Algebra.Com's Answer #696610 by Edwin McCravy(20060)\"\" \"About 
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document.write( "From the universal set {1,2,...,100},\r\n" );
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document.write( "A = the subset of multiples of 5\r\n" );
document.write( "B = the subset of multiples of 8\r\n" );
document.write( "A and B = the subset of multiples of both 5 and 8, i.e., \r\n" );
document.write( "multiples of 40\r\n" );
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document.write( "N(A or B) = N(A) + N(B) - N(A and B)\r\n" );
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document.write( "There are 100/5 = 20 multiples of 5, so N(A) = 20\r\n" );
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document.write( "There are 100/8 = 12.5, round down to 12 multiples of 8, \r\n" );
document.write( "so N(B) = 12\r\n" );
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document.write( "There are 100/40 = 2.5, round down to 2 multiples of 40, \r\n" );
document.write( "so N(A and B) = 2\r\n" );
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document.write( "N(A or B) = N(A) + N(B) - N(A and B) = 20 + 12 - 2 = 30\r\n" );
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document.write( "Edwin
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