Add days to a date in PHP

Question

Is there any php function available where I can add days to a date to make up another date? For example, I have a date in the following format: 27-December-2011

If I

Answer 1

$registered = $udata->user_registered;
$registered = date( "d m Y", strtotime( $registered ));
$challanexpiry = explode(' ', $registered);
$day   = $challanexpiry[0];
$month = $challanexpiry[1];
$year  = $challanexpiry[2];
$day = $day+10;
$bankchallanexpiry = $day . " " . $month . " " . $year;