If you would like to get the amount of hours between 10:00 and 12:00 then use this!

[code lang=”php”]
function timeDiff($firstTime,$lastTime) {
$firstTime=strtotime($firstTime);
$lastTime=strtotime($lastTime);
$timeDiff=$lastTime-$firstTime;
return $timeDiff;
}

echo (timeDiff(“10:00″,”12:00”)/60)/60;
[/code]