document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189471>Question 1189471</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A curious card-player wrote the numbers 1,2,3,…,50 on fifty cards and spread them out in front of him. First, he flipped all the cards over so that they were all face down. Next, he flipped all the cards that had even numbers. Then, he proceeded to flip all the cards with numbers divisible by 3, then 4,5 and so on up to 50. What is the sum of the numbers on the cards that were left face down at the end? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #820828 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52852)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=820828\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .\r<BR>\n" );
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document.write( "This problem was solved at the forum several years ago by tutor @KMST.\r<BR>\n" );
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document.write( "See the link\r<BR>\n" );
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document.write( "<A  rel=nofollow HREF=https://www.algebra.com/algebra/homework/word/geometry/Geometry_Word_Problems.faq.question.1105590.html>https://www.algebra.com/algebra/homework/word/geometry/Geometry_Word_Problems.faq.question.1105590.html</A>\r<BR>\n" );
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document.write( "https://www.algebra.com/algebra/homework/word/geometry/Geometry_Word_Problems.faq.question.1105590.html\r<BR>\n" );
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document.write( "She shown that the selected numbers are all the perfect squares between 1 and 50 inclusive 1, 4, 9, 16, 25, 36, 49,\r<BR>\n" );
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document.write( "so their sum is  1 + 4 + 9 + 16 + 25 + 36 + 49 = 140.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<U>ANSWER</U><BR>\n" );
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