document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=309626>Question 309626</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mary (m) is 4 years older than Rico (r).  Ten years ago Mary was 3 times as old as Rico was then.  a) how old are they now? b) determine if answer is correct by checking that it satisfies the conditions of the problem\r<BR>\n" );
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document.write( "I've got r = 4 = m and have to subtract 10 years from both and multiply both by 3?\r<BR>\n" );
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document.write( "3(r-10) = m -10<BR>\n" );
document.write( "3r - 30 = m -10<BR>\n" );
document.write( "m = 3r - 20<BR>\n" );
document.write( "r + 4 = 3r - <BR>\n" );
document.write( "4 + r = -20 + 3r (subtract 3r from both sides)<BR>\n" );
document.write( "4 + -2r = -20  (subtract 4 from both sides)<BR>\n" );
document.write( "-2r = -24 (divide both by -2) gives the solution of 12?\r<BR>\n" );
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document.write( "so if I was solving for r, then that is Rico's age 10 years ago?? He would be 22 now and if 4 years older, Mary would be 26?  This can't be right if 10 years ago she was 3 times his age.  \r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #221444 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=221444\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Mary (m) is 4 years older than Rico (r).<BR>\n" );
document.write( "Write an equation for this statement first:<BR>\n" );
document.write( "m = r+4<BR>\n" );
document.write( " Ten years ago Mary was 3 times as old as Rico was then. <BR>\n" );
document.write( "a) how old are they now?<BR>\n" );
document.write( "I've got r = 4 = m?????? and <BR>\n" );
document.write( "have to subtract 10 years from both and multiply both by 3?<BR>\n" );
document.write( "3(r-10) = m - 10<BR>\n" );
document.write( "3r - 30 = m -10<BR>\n" );
document.write( "Correct up to here, now<BR>\n" );
document.write( "3r = m - 10 + 30<BR>\n" );
document.write( "3r = m + 20<BR>\n" );
document.write( "Replace m with (r+4)<BR>\n" );
document.write( "3r = (r+4) + 20<BR>\n" );
document.write( "3r - r = 24<BR>\n" );
document.write( "2r = 24<BR>\n" );
document.write( "r = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=24%2F2 ALIGN=MIDDLE  ALT=\"24%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "r = 12 yrs is Rico's present age<BR>\n" );
document.write( "and we know<BR>\n" );
document.write( "m = r + 4<BR>\n" );
document.write( "m = 12 + 4<BR>\n" );
document.write( "m = 16 yrs is Mary's present age<BR>\n" );
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document.write( "b) determine if answer is correct by checking that it satisfies the conditions of the problem<BR>\n" );
document.write( "Check solution in the statement:<BR>\n" );
document.write( "\" Ten years ago Mary was 3 times as old as Rico was then. \"<BR>\n" );
document.write( "16 - 10 = 3(12 - 10)<BR>\n" );
document.write( "6 = 3(2); confirms the solutions<BR>\n" );
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document.write( "Did this help straighten things out for you? </SPAN>\n" );
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