JSFiddle - React, Tailwind, and code Playground

HTML

<div id='date'>April 15, 2014</div>
<div id='num' >10</div>
<div id='count'>0</div>

JavaScript

console.clear();
var num = $('#num');
var count = $('#count');
var x = +$(num).text();
var result = 0;

var start = new Date($('#date').text());
var now = new Date();
var times = (now - start)/1000/60/60;

for(i = 0 ;i != times.toFixed(0);i++){
  result = result +  x/100*4.8;
  $(count).text(result.toFixed(2));
}

var timer = setInterval(function(){
  var result = 0;
  var times = (now - start)/1000/60/60;
  $(count).text(result.toFixed(2));
  for(i = 0 ;i != times.toFixed(0);i++){
      result = result +  x/100*4.8;
      $(count).text(result.toFixed(2));
  }
},1000);