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Uh, because the same classes also fulfill the graduate requirements.</p>
<p>Look, you don’t have to believe me – it’s all on the web. [Here[/url</a>] is the page with Sloan’s undergrad requirements; if you click on “core subjects” or “areas of concentration” it will take you to the page which lists the individual classes, and if you click on the individual classes you will see that most of them are marked “G” for graduate. (List of symbols is [url=<a href=“http://student.mit.edu/catalog/symbols.html]here[/url]”>MIT Subject Listing & Schedule Symbol Definitions]here](<a href=“http://mitsloan.mit.edu/undergrad/ac-main.php]Here[/url”>http://mitsloan.mit.edu/undergrad/ac-main.php)</a>.)</p>
<p>It’s not really such an unusual thing at MIT – undergrads are pretty free to take graduate classes in any department if they choose to do so.</p>