Round a Number in JavaScript after a Calculation with Math.round : I don't get `Math.round(num * 100) / 100` to work. I use normal jQuery and i don't get it... Thankful for every help. Thanks!

This scripts convert a length, its work perfect

    <script>
    var meters = document.getElementsByClassName("num");
    for (var i = 0; i < meters.length; i++) {
      meters[i].innerHTML = parseInt(meters[i].innerHTML) * 3.2808399; 
    }
    </script>

    <p class="num">12</p>
    <p class="num">7</p>