document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=34935>Question 34935</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Anothe one that is confusing to me.  Thank you for your help! THIS IS A HARD ONE!\r<BR>\n" );
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document.write( "Solve any way and show work.<BR>\n" );
document.write( "How many 3-digit numbers are possible using 2,3,5, or 7 if you DO NOT repeat digits? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #21190 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=21190\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> OK long way first:\r<BR>\n" );
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document.write( "235 325 523 723<BR>\n" );
document.write( "237 327 527 725<BR>\n" );
document.write( "253 352 532 732<BR>\n" );
document.write( "257 357 537 735<BR>\n" );
document.write( "273 372 572 752<BR>\n" );
document.write( "275 375 573 753\r<BR>\n" );
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document.write( "there are no other 3 digit numbers made up from 2,3,5 or 7.\r<BR>\n" );
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document.write( "So... \"quick\" method:<BR>\n" );
document.write( "Think of the number like ABC... how many numbers could be placed in position A? Answer any of the 4.<BR>\n" );
document.write( "OK, so we have a number in position A. Whatever it is, we now have 3 numbers left to put into position B, so altogether we have 4*3 possibilities.<BR>\n" );
document.write( "And finally we have 2 numbers to put into position C, so altogether we have 4*3*2 permutations --> 24.\r<BR>\n" );
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document.write( "Count the number of examples i wrote at the start: there are 24 different 3 digit numbers.\r<BR>\n" );
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document.write( "jon </SPAN>\n" );
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