[jQuery] Major Problem With Dom Traversal

[jQuery] Major Problem With Dom Traversal

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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<body bgcolor="#ffffff" text="#000000">
<font face="Arial">Working on a page with a table of about 10,000 rows
and 30 div's, the following takes about 5 seconds....
    $("div.siteWidth").css("width", modifiedW);
What am I doing wrong? How can the table be bypassed?
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</body>
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