document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=619063>Question 619063</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many possible security codes can be made using 4 digits followed by 3 letters if (a) digits and letters can be repeated and (b) digits and letters can not be repeated? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #389314 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=389314\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">     How many possible security codes can be made using 4 digits followed by 3 letters if <BR>\n" );
document.write( "(a) digits and letters can be repeated<BR>\n" );
document.write( "10*10*10*10*26*26*26 = 175,760,000<BR>\n" );
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document.write( "(b) digits and letters can not be repeated?<BR>\n" );
document.write( "10*9*8*7*26*25*24 = 78,624,000 </SPAN>\n" );
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