document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1171548>Question 1171548</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Last year Jason's age was a prime number. This year it is a square number. How old is he this year? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #796453 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=796453\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The first tutor missed the point of the problem; there is only one solution.<br><BR>\n" );
document.write( "His age this year is a square number; let it be x^2.<br><BR>\n" );
document.write( "That means last year his age was x^2-1.<br><BR>\n" );
document.write( "But x^2-1 = (x-1)(x+1), which is the product of two integers.  The only way the product of two integers can be prime is if one of them is 1.<br><BR>\n" );
document.write( "So x-1 is 1, making x=2 and x+1=3.  So his age last year was 1*3=3, making his age this year 4.<br><BR>\n" );
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