price.js

'use strict';

var $choices = $('.choice');
var $total = $('.total .number');

$choices.on('click', function (event) {
    var price = $(this).data('price');
    $total.text(price);
    changeNumber('.total .number');
});

function getRandomNumber(max) {
    return Math.floor(Math.random() * 10);
}

function getRandomDigits() {
    var randoms = [];
    var int;

    while (randoms.length < 10) {
        int = getRandomNumber(10);

        if ((randoms.indexOf(int) === -1)) {
            randoms.push(int);
        }
    }

    return randoms;
}

function changeNumber() {
    var digits = $total.text().split('');
    var $digits;

    $total.text('');

    $digits = digits.map(function (digit, index) {
        var $span = $('<span>').addClass('digit').text(digit);

        $total.append($span);

        return $span;
    });

    Array.prototype.forEach.call(digitSpans, function (span) {
        var value = span.innerText;
        var randoms = getRandomDigits();
        var i = 0;
        var interval = setInterval(function () {
            span.innerText = randoms[i];
            i += 1;
            if (i === randoms.length) {
                clearInterval(interval);
                span.innerText = value;
            }
        }, 25);
    });
}