quiz.html

<script>
    // your code goes here
</script>

<script>
var a = 3;
z = 5;

(function() {
    var a = 3 + 5,
        b =  a / 2,
        str = "Inter" + "polation";

    z = z + 1;

    res = (a + b + z) * 3;

    // will output 'Interpolation: (8 + 4 + 6) * 3 = 54'
    console.log('#{str}: (#{a} + #{b} + #{z}) * 3 = #{res}'.interpolate());
}).run();
</script>