I think showing an example would be the best way to answer this question. Check out this JSFiddle.
HTML:
<ul>
<li>
<a href="#">
<img alt="placeholderImg" src="http://placehold.it/82x82">
</a>
</li>
<li>
<a href="#">
<img alt="placeholderImg" src="http://placehold.it/82x82">
</a>
</li>
<li>
<a href="#">
<img alt="placeholderImg" src="http://placehold.it/82x82">
</a>
</li>
</ul>
My goal is to ensure that my floated list items have a consistent width of 262px in all popular browsers (including IE7 and later).