title: Add numbers from variables in Google Apps Script going strange
body: <p>When adding numbers which I pull off a CSV, this is the logfile I am getting:</p>
  
  <pre><code>var costs = Number(csvData[i][9].replace(",","."));  // need to replace , with . and    
  total_costs_overeenkomst=total_costs_overeenkomst+costs;   // add variables
  Logger.log("Kosten: "+costs);
  Logger.log("Subtotaal:"+total_costs_overeenkomst);
  </code></pre>
  
  <p>Here is the log, is goes well until the 3rd, where I get a strange rounding error:</p>
  
  <pre><code>Kosten:4.8
  Subtotaal:4.8
  Kosten:49.92
  Subtotaal:54.72
  Kosten:4.8
  Subtotaal:59.519999999999996
  Kosten:2.4
  Subtotaal:61.919999999999995
  Kosten:2.57
  Subtotaal:64.49
  Kosten:22.18
  Subtotaal:86.66999999999999
  Kosten:34.56
  Subtotaal:121.22999999999999
  Kosten:4.8
  Subtotaal:126.02999999999999
  </code></pre>
  
  <p>Why is this happening?</p>
  
  <p>Kind regards,
  Riel</p>