document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=799232>Question 799232</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how many numbers consisting of the digits from 3,5,7,9 can be made if (a)each digit is to be used only once (b) repetition is allowed. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #482587 by </B><A HREF=/tutors/aboutme.mpl?userid=thejackal><B>thejackal(72)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=thejackal><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=thejackal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=482587\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> n = 4, there 4 types of values you can choose from i.e. 3,5,7 or 9<BR>\n" );
document.write( "r = 4, of these 4types you must produce a combination that has 4 digits\r<BR>\n" );
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document.write( "thus the total number of possible combinations is found using the formula\r<BR>\n" );
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document.write( "(n+r-1)!/r!(n-1)!\r<BR>\n" );
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document.write( "if and only if repetitions are allowed.\r<BR>\n" );
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document.write( "Combinations with repetition (n=4, r=4)\r<BR>\n" );
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document.write( "35 entries.<BR>\n" );
document.write( "{3,3,3,3} {3,3,3,5} {3,3,3,7} {3,3,3,9} {3,3,5,5} {3,3,5,7} {3,3,5,9} {3,3,7,7} {3,3,7,9} {3,3,9,9} {3,5,5,5} {3,5,5,7} {3,5,5,9} {3,5,7,7} {3,5,7,9} {3,5,9,9} {3,7,7,7} {3,7,7,9} {3,7,9,9} {3,9,9,9} {5,5,5,5} {5,5,5,7} {5,5,5,9} {5,5,7,7} {5,5,7,9} {5,5,9,9} {5,7,7,7} {5,7,7,9} {5,7,9,9} {5,9,9,9} {7,7,7,7} {7,7,7,9} {7,7,9,9} {7,9,9,9} {9,9,9,9} </SPAN>\n" );
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