document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1039326>Question 1039326</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An auditorium has 20 seats on the first row, 24 seats on the second row, 28 seats on the third row, and so on and has 30 rows of seats. How many seats are in the theatre?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #654059 by </B><A HREF=/tutors/aboutme.mpl?userid=addingup><B>addingup(3677)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=addingup><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=addingup><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=654059\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 20+21+22+23+24+25+26+27+28+29+30 = 275<BR>\n" );
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document.write( "But here is a shortcut to adding consecutive numbers:<BR>\n" );
document.write( "Add the smallest number to the largest number of the given set of consecutive numbers. Then multiply the result by the number of numbers in the set. Finally divide the result by two:<BR>\n" );
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document.write( "20+30= 50 and from 20 to 30, BOTH INCLUDED, we have 11 numbers:<BR>\n" );
document.write( "50*11 = 550<BR>\n" );
document.write( "550/2 = 275<BR>\n" );
document.write( "so there you have it.<BR>\n" );
document.write( "John </SPAN>\n" );
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