document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=535615>Question 535615</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me to solve this question : \r<BR>\n" );
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document.write( "How many different numbers can be formed by taking one, two, three and four digits from the digits 1, 2, 7 and 8, if repetition are not allowed?\r<BR>\n" );
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document.write( "can I do it this way :\r<BR>\n" );
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document.write( "  4P1 x 4P2 x 4P3 x 4P4<BR>\n" );
document.write( "= 4 x 12 x 24 x 24<BR>\n" );
document.write( "= 27648<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 #351959 by </B><A HREF=/tutors/aboutme.mpl?userid=htmentor><B>htmentor(1343)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=htmentor><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=htmentor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=351959\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You are correct in assuming this is a permutation problem.  However, to find the <BR>\n" );
document.write( "total number, the operation required is addition, not multiplication:<BR>\n" );
document.write( "N = P(4,1) + P(4,2) + P(4,3) + P(4,4) = 4 + 12 + 24 + 24 = 64 </SPAN>\n" );
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