How to avoid black bars on flash embed?

I need a hulu embed video to be 620px in width, what should I set the height to so I don't get the black bars on the sides. I tried to look up aspect ratio calculators online but they all seem to ask for what aspect ratio I need, etc. I don't know what I need exactly, I just want to enter a width and get the height that will prevent those black bars. Anyone know what the height value would be?

Sample hulu embed code:

<object width="620" height="288">
    <param name="movie" value="http://www.hulu.com/embed/xtgQtVlTW2odUKvjgvN6ig"></param>
    <param name="allowFullScreen" value="true"></param>
    <embed src="http://www.hulu.com/embed/xtgQtVlTW2odUKvjgvN6ig" type="application/x-shockwave-flash"  width="620" height="288" allowFullScreen="true"></embed>
</object>

Solution

No need for an aspect ratio calculator, a regular calculator can do the trick, too.

620/512 = 1,2109375 x 288 = 348,75

So set the height to 349, and you'll be fine...