document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=84121>Question 84121</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many different two-digit numbers can be formed using the digits 1, 3, 4, and 5. Repetition of digits is allowed. \r<BR>\n" );
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document.write( "How many 7-digit phone numbers can be formed if the first digit cannot be 0 and repetition of digits is allowed? <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 #60542 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=60542\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many different two-digit numbers can be formed using the digits 1, 3, 4, and 5. Repetition of digits is allowed.<BR>\n" );
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document.write( "4*4 = 16 two-digit numbers<BR>\n" );
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document.write( "How many 7-digit phone numbers can be formed if the first digit cannot be 0 and repetition of digits is allowed? \r<BR>\n" );
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document.write( "ways to choose the first digit = 9<BR>\n" );
document.write( "ways to choose remaining 6 digits = 10^6<BR>\n" );
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document.write( "Total number of 7-digit phone numbers = 9*10^6 = 9 million\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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