document.write( "Question 485428: A student is allowed to choose a number at random from counting numbers 60 to 100 inclusive (60, 61, 62, 63,... 97, 98, 99, 100). Using the grading scheme of 60-69=D, 70-79=C, and so on. What is the probability that student gets an A grade? \n" ); document.write( "
Algebra.Com's Answer #332004 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "60, 61, 62, 63,... 97, 98, 99, 100.\r\n" );
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document.write( "To find the denominator of the probability:\r\n" );
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document.write( "The mistake most people would make here is to assume that there\r\n" );
document.write( "are 100-60 or 40 possible grades, when there are really 41 possible\r\n" );
document.write( "grades.  The reason it's 41 and not 40 is this:\r\n" );
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document.write( "1.  There are 100 numbers from 1 to 100\r\n" );
document.write( "2.  We don't count the numbers from 1 to 59, and there are 59 of them.\r\n" );
document.write( "3.  Therefore the number of numbers from 60 to 100 inclusive is 100-59 or 41.\r\n" );
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document.write( "To find the numerator of the probability\r\n" );
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document.write( "The same kind of mistake most people would make here is to assume that \r\n" );
document.write( "there are 100-90 or 10 possible A grades, when there are really 11 \r\n" );
document.write( "possible A grades.  The reason it's 11 and not 10 is because\r\n" );
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document.write( "1.  There are 100 numbers from 1 to 100\r\n" );
document.write( "2.  We don't count the numbers from 1 to 89, and there are 89 of them.\r\n" );
document.write( "3.  Therefore the number of numbers from 90 to 100 inclusive is 100-89 or 11.\r\n" );
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document.write( "So the probability is 11/41.    \r\n" );
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document.write( "Edwin
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