document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=606466>Question 606466</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Here is the problem I am having trouble with (one of the practice question in a subject test study guide book for Math 1):\r<BR>\n" );
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document.write( "A random number generator will randomly select an integer between 1 and 100, inclusive.  What is the probability that the integer selected will be a product of two  odd integers greater than 1?\r<BR>\n" );
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document.write( "A) 25/100\r<BR>\n" );
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document.write( "B) 26/100\r<BR>\n" );
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document.write( "C) 28/100\r<BR>\n" );
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document.write( "D) 29/100\r<BR>\n" );
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document.write( "E) 30/100\r<BR>\n" );
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document.write( "So, I decided that the integer described must not be a prime number and must be odd itself.  I counted how many odd number there are between 1 and 10, then between 11 and 20, then between 21 and 30.  There are 4 of them in the first sequence, 5 of them in the second, and 5 of them in the third.  There are ten sets of ten in 100, so there are 5(9)+4 odd numbers between 1 and 100, which is 49.  \r<BR>\n" );
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document.write( "The next step is to subtract the # of prime numbers there are from this, but how can i figure out the # of prime #s without having to list them one by one?  Thats is quite time consuming...\r<BR>\n" );
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document.write( "Thank you!   </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #382099 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20055)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=382099\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "You have no choice but to list the primes, but don't forget to rule out 1,\r\n" );
document.write( "also.\r\n" );
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document.write( "50 of the numbers between 1 and 100 are even and 50 are odd.\r\n" );
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document.write( "The only odd numbers which are not the product of two odd integers \r\n" );
document.write( "greater than 1 are 1 and these 24 odd primes\r\n" );
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document.write( "3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97\r\n" );
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document.write( "So that makes 25 of the 50 odd numbers that are not the product of \r\n" );
document.write( "two odd  integers greater than 1. So the other 25 odd numbers are, so\r\n" );
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document.write( "the answer is 25 out of 100, 25/100, choice A. \r\n" );
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document.write( "Edwin</PRE> </SPAN>\n" );
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