document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=229101>Question 229101</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many combinations of three digits can be made from the numbers 0-9 without repetitions?\r<BR>\n" );
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document.write( "Please correct my answer if its wrong.\r<BR>\n" );
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document.write( "n=10<BR>\n" );
document.write( "r=3\r<BR>\n" );
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document.write( "nPr=(n!)/(n-r)!<BR>\n" );
document.write( "   = (10!)/(10-3)!<BR>\n" );
document.write( "   = (3,628,800)/ (7)!<BR>\n" );
document.write( "   = (3,628,800)/5040<BR>\n" );
document.write( "   = 720 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #169927 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=169927\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many combinations of three digits can be made from the numbers 0-9 without repetitions? <BR>\n" );
document.write( "Please correct my answer if its wrong. <BR>\n" );
document.write( "n=10<BR>\n" );
document.write( "r=3 <BR>\n" );
document.write( "nPr=(n!)/(n-r)!<BR>\n" );
document.write( "= (10!)/(10-3)!<BR>\n" );
document.write( "= (3,628,800)/ (7)!<BR>\n" );
document.write( "= (3,628,800)/5040<BR>\n" );
document.write( "= 720<BR>\n" );
document.write( "-------------------<BR>\n" );
document.write( "You want combinations, not permutations.<BR>\n" );
document.write( "Permutations are arrangements: Example 231 is different than 312<BR>\n" );
document.write( "Combinations are groups: Example 231 is the same group as 312 <BR>\n" );
document.write( "10C3 = 10!/[7!*3!] = 120<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );