document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1015951>Question 1015951</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mike is twice as old as his sister. Together, their ages add up to 30. How old are Mike and his sister? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #632338 by </B><A HREF=/tutors/aboutme.mpl?userid=fractalier><B>fractalier(6550)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=fractalier><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=fractalier><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=632338\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Call Mike's and his sister age, m and s.  Then we have<BR>\n" );
document.write( "m = 2s  and<BR>\n" );
document.write( "m + s = 30<BR>\n" );
document.write( "Substitute the first equation into the second and get<BR>\n" );
document.write( "2s + s = 30<BR>\n" );
document.write( "3s = 30<BR>\n" );
document.write( "s = 10  and then<BR>\n" );
document.write( "m = 20 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );