need help in rounding off into two decimal places

[newphpbees]

Hi..

I have javascript code with computation, but I have problem in my result because it was not round off or fixed into two decimal places only.

here is my code:

<script type="text/javascript">

function test_(cmpd) {
    var len_ = (document.frmMain.elements.length) - 1;
  
     for (i=0; i <= len_; i++ ) {   
    
       var strPos_ = document.frmMain.elements[i].id.indexOf(cmpd)
         
   
              if (strPos_ != -1) {
              var strPos = document.frmMain.elements[i].id.indexOf("_");
              
var strId = document.frmMain.elements[i].id.slice(strPos + 1) + "_" + document.frmMain.elements[i].id.slice(0,strPos)               
     // this is the computation that I need to fixed the result into two decimal places
    document.frmMain.elements[i].value = document.getElementById(strId).value * document.getElementById('mult').value;  
     } 
    }  
}
</script>

Thank you so much