How to calculate comparation percentage of 2 arrays?

Question

How can I get a percentage of right answers if I have 2 arrays in PHP or javascript, preferably in PHP?

So, I have these two arrays and I want to compare a quiz result with the correct answers and get a percentage score:

$quiz_results = array( 'q1' => 'no',
                    'q2' => 'yes',
                    'q3' => 'no',
)

$answers = array( 1 => 'yes',
                  2 => 'no',
                  3 => 'yes'
)

Answer 1

Run through the answers and compare them to the questions. If they are the same increment the correct answer count.

$quiz_results = array( 'q1' => 'yes',
                    'q2' => 'yes',
                    'q3' => 'no',
);
$answers = array( 1 => 'yes',
                  2 => 'no',
                  3 => 'yes'
);

$totalquestions = count($answers);
$correct = 0;
foreach($answers as $key => $answer){
    //q + the key should do it. Its easier if they are the same obviously
    if($answer == $quiz_results['q'.$key]){
        // correct 
        $correct++;
    }
}

echo 100 / $totalquestions * $correct; //returns 33.333333%