You'll need a combination of CSS and HTML (and optionally PHP). Create a div of both the p element and the img element...like this:
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<div>
<img src="yourimage">
<p>Some text.</p>
</div>
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The CSS property you want is float. You can either use CSS as a property in the div tag...
<div style="float:right">
...or as external CSS (recommended if you use a lot of CSS).
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.your_class_name_here{
float: right;
}
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If you know PHP, I would recommend sticking the HTML code in a PHP function so you won't have to keep creating the same darn divs.