document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1138074>Question 1138074</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An identification code is to consist of 4 letters followed by 3 digits. Determine the following.<BR>\n" );
document.write( "​a) How many different codes are possible if repetition of letters is ​permitted, repetition of numbers is not​ permitted, and the first three entries must all be the same​ letter?<BR>\n" );
document.write( "​b) How many different codes are possible if the first letter must be an ​A, ​B, ​C, or D and repetition is not​ permitted? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #755985 by </B><A HREF=/tutors/aboutme.mpl?userid=VFBundy><B>VFBundy(438)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=VFBundy><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=VFBundy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=755985\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <b>a) How many different codes are possible if repetition of letters is ​permitted, repetition of numbers is not​ permitted, and the first three entries must all be the same​ letter?</b><BR>\n" );
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document.write( "26 * 1 * 1 * 26 * 10 * 9 * 8 = 486,720<BR>\n" );
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document.write( "<b>​b) How many different codes are possible if the first letter must be an ​A, ​B, ​C, or D and repetition is not​ permitted?</b><BR>\n" );
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document.write( "4 * 3 * 2 * 1 * 10 * 9 * 8 = 17,280 </SPAN>\n" );
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