How would I find the answer to X% of X in PHP?

问题

I have two variables:

$percent = '3.5'; //this is the percentage
$order = 400;
//so how would i get $percent of $order?

Now in PHP how would I find out what 3.5% of 400 is (I know its 14) - but would like to know how to calculate it directly in PHP using those two variables above.

Appreciate your response.

回答1:

"Percent" just means "per 100" or "over 100" or "/ 100"

$percentOfOrder = $order * ($percent / 100);

回答2:

You could make a percentOf function:

function percentOf($number, $percent){
    return $number * ($percent / 100);
}

//then:
echo percentOf($order, $percent);

Demo: http://codepad.org/a6BgEEs2

来源：https://stackoverflow.com/questions/8316558/how-would-i-find-the-answer-to-x-of-x-in-php