document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=339817>Question 339817</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Consider the old rules for telephone are codes determined by creating three digit codes with 0 or 1 as the second digit but excluding codes ending in 00 or 11 as these were reserved for toll-free calls, emergency services, and other special uses. How many different codes were possible under these rules? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #243598 by </B><A HREF=/tutors/aboutme.mpl?userid=jrfrunner><B>jrfrunner(365)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jrfrunner><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=jrfrunner><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=243598\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> based on how you defined the problem, there are 3 numbers to choose<BR>\n" );
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document.write( "first number can be any digit so there are 10 choices<BR>\n" );
document.write( "second number can be only 0 or 1 so there are 2 choices<BR>\n" );
document.write( "third number can not include 0 if the second number is 0 or cannot include 1 if the second number is a 1, so there are 9 choices available <BR>\n" );
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document.write( "answer:  10*2*9=180 </SPAN>\n" );
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