$total_time = $end_time - $begining_time;
# get the total minutes
$minutes = ($total_time / 60);
# get the reminader for seconds
$seconds = ($total_time % 60);
# get the total hours
$hours = ($minutes / 60);
# and re-adjust minutes to be just the minutes
$minutes = ($minutes % 60);
# I use printf here to make sure we have integers
printf "%d hours, %d minutes, %d seconds", $hours, $minutes, $seconds;