document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=392603>Question 392603</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how many different 4-digit numbers can be formed from th digits 2, 3, 4,5,6,7,and 8  if:<BR>\n" );
document.write( "       a)repetition of digits is not allowed?<BR>\n" );
document.write( "       b)repetition of digits is  allowed?<BR>\n" );
document.write( "       c)how many of them are odd numbers? refer to (a).<BR>\n" );
document.write( "       d)how many of them are even numbers? refer to (b). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #278732 by </B><A HREF=/tutors/aboutme.mpl?userid=sudhanshu_kmr><B>sudhanshu_kmr(1152)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sudhanshu_kmr><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=sudhanshu_kmr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=278732\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> there are 4 even and 3 odd numbers....\r<BR>\n" );
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document.write( "a)<BR>\n" );
document.write( " no. of ways to form 4 digit numbers without repetition = 7P4 = 840\r<BR>\n" );
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document.write( "b) no. of ways to form 4 digit numbers with repetition = 7*7*7*7 = 7^4 = 2401\r<BR>\n" );
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document.write( "c) we can put odd digit on unit place be 3 ways and can arrange remaining 6 \r<BR>\n" );
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document.write( "digit on first 3 places by 6P3 ways, \r<BR>\n" );
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document.write( "no. of odd numbers ( refer to a )  = 6P3 *  3 = 360\r<BR>\n" );
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document.write( "d) for unit place we can put digit by 4 ways and for other 3 places any digit\r<BR>\n" );
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document.write( " no. of even numbers when repetition is allowed = 7*7*7*4 =1372\r<BR>\n" );
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document.write( "  </SPAN>\n" );
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