document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=890095>Question 890095</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Which of the following expressions shows the number of 8 character passwords that can be formed using letters and digits if the password must begin with a letter?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #538793 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=538793\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the number of letters in the alphabet is equal to 26 (a to z)<BR>\n" );
document.write( "the number of numbers in a 1 digit number is equal to 10 (0 to 9)\r<BR>\n" );
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document.write( "if the first character has to be a letter, then you have 26 possible choices for that first character.<BR>\n" );
document.write( "if the other characters can be a letter or a number, than you have 36 possible choices for each of the other 7 characters.\r<BR>\n" );
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document.write( "the number of possible choices is therefore 26 * 36^7.\r<BR>\n" );
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document.write( "if you allow for capital and small letters, then the number of characters in the alphabet becomes 52.\r<BR>\n" );
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document.write( "if those are not any of your choices, let me know what the choices are and i'll pick one for you if i can figure out what they're looking for.\r<BR>\n" );
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document.write( "the total number of choices then becomes 52 * 62^7\r<BR>\n" );
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document.write( "26 * 36^7 = 2.037... * 10^12\r<BR>\n" );
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document.write( "52 * 62^7 = 1.831... * 10^14\r<BR>\n" );
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document.write( "you can use your calculator to get the whole number if you need that.\r<BR>\n" );
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document.write( "when the calculator shows E14, that means * 10^14.\r<BR>\n" );
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