document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=541021>Question 541021</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if i have ten digits (0-9) how many 4 digit codes can i make? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #353988 by </B><A HREF=/tutors/aboutme.mpl?userid=jpg7n16><B>jpg7n16(66)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jpg7n16><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=353988\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is a combination problem. Really you are looking for how many options do you have at each spot. Your \"code\" has 4 spots open:<BR>\n" );
document.write( "(__-__-__-__)<BR>\n" );
document.write( "And you just need to know if there are any limitations on them. The problem doesn't say you can't reuse a number, so you have 10 options for each spot. <BR>\n" );
document.write( "(10-10-10-10)<BR>\n" );
document.write( "To figure out how many different codes you could make, multiply the spots together.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2810%29%2A%2810%29%2A%2810%29%2A%2810%29=10000 ALIGN=MIDDLE  ALT=\"%2810%29%2A%2810%29%2A%2810%29%2A%2810%29=10000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
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document.write( "If you run across a problem where you cannot reuse the numbers, here's what you'd do. You would have 10 numbers for the 1st slot, but only 9 for the second (since you used one of them in the first slot), then 8 for the 3rd, etc. To solve a problem like this, do the same thing:<BR>\n" );
document.write( "(10-9-8-7)<BR>\n" );
document.write( "And multiply together.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2810%29%2A%289%29%2A%288%29%2A%287%29=5040 ALIGN=MIDDLE  ALT=\"%2810%29%2A%289%29%2A%288%29%2A%287%29=5040\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Future problem solved!<BR>\n" );
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