document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=89817>Question 89817</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do you determine the units digit of 3 to the 99th power??? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #65235 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=65235\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3^1=3 ... 3^2=9 ... 3^3=27 ... 3^4=81 ... 3^5=243 (same units digit as 3^1)\r<BR>\n" );
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document.write( "the unit digits repeat in a pattern of four ... 99 divided by 4 is 24 with a remainder of 3\r<BR>\n" );
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document.write( "so the units digit for 3^99 is the third units digit in the pattern, which is 7 </SPAN>\n" );
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