[EfrainSanmiguel]

hola a todos.. ya llegua a la solucion aqui les dejo el codigo..

script language="javascript">  
function calcula(operacion)
{  
var operando1 = document.getElementById('montoLegal').value; 
    operando1= operando1.replace(".","").replace(",","");
 var operando2 = document.getElementById('creditoadicional').value; 
 operando2= operando2.replace(".","").replace(",","");
 var result = eval(operando1 + operacion + operando2);
 document.getElementById('total').value = result ;}  
</script>

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