https://artofproblemsolving.com/wiki/index.php?title=2013_PMWC_Problems/Problem_I1&feed=atom&action=history2013 PMWC Problems/Problem I1 - Revision history2024-03-29T01:37:50ZRevision history for this page on the wikiMediaWiki 1.31.1https://artofproblemsolving.com/wiki/index.php?title=2013_PMWC_Problems/Problem_I1&diff=72926&oldid=prevIhightower: answer for q12015-11-19T17:02:19Z<p>answer for q1</p>
<p><b>New page</b></p><div>I think it should be 5.<br />
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sum of 1 to 9.. is 9x10/2 =45<br />
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total cards with them.. is 40<br />
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so 5 is the left out one.</div>Ihightower