document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1098316>Question 1098316</A>: <I><SPAN STYLE=\"word-break: break-all;\"> given the sum S10=910 of an arithmetic sequence & A20=95, find A1? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #712677 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13215)</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=712677\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br>Let a be the first term and d be the common difference.<br><BR>\n" );
document.write( "If the sum of the first 10 terms of an arithmetic sequence is 910, then that sum of 910 is the sum of 5 pairs of numbers, each with a sum of 910/5 = 182. One of those pairs is the sum of the first and tenth numbers.<br><BR>\n" );
document.write( "The first number is a; the 10th number is a+9d: so<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+%2B+a%2B9d+=+182 ALIGN=MIDDLE  ALT=\"a+%2B+a%2B9d+=+182\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2a%2B9d+=+182 ALIGN=MIDDLE  ALT=\"2a%2B9d+=+182\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The 20th term, 95, is a+19d:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%2B19d+=+95 ALIGN=MIDDLE  ALT=\"a%2B19d+=+95\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "That gives you two equations in a and d which you can solve to find the answer to the problem.<br><BR>\n" );
document.write( "But I'm wondering if you have shown the right numbers, because with the numbers you show, the terms of the sequence turn out to be ugly fractions.<br><BR>\n" );
document.write( "So I'm not going to show the ugly arithmetic; you can solve the pair of equations on your own. </SPAN>\n" );
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