php trim price

I am trying to create an allposters site after reading the review.
Well everything is coming along fine until I went to print the price out. It seems they use a four digit decimal for some reason. Example: $32.0000
Well I looked at php.net under the trim function but couldn't find anything on how to trim from the end. Does anyone have any ideas on how to do this?

If you're inserting into a DB you could set the mysql field parameters to use just 2 decimals.

and if you're not,
$price = round($price, 2);

trim is used to eliminate whitespace at the end of a string

Thanks guys. I am storing the info in a db but didn't think of doing it that way. Thanks a ton for both answers!